Co-reporter:Yanfang Geng, Shuai Wang, Mengqi Shen, Ranran Wang, Xiao Yang, Bin Tu, Dahui Zhao, and Qingdao Zeng
ACS Omega September 2017? Volume 2(Issue 9) pp:5611-5611
Publication Date(Web):September 8, 2017
DOI:10.1021/acsomega.7b00891
The self-assemblies of polycyclic aromatic diimide (PAI) compounds on solid surfaces have attracted great interest because of the versatile and attractive properties for application in organic electronics. Here, a planar guest species (coronene) selectively adsorbs on the helicene-typed PAI1 monolayer strongly, depending on the conjugated cores of these PAIs. PAI1 molecule displays evidently a bowl structure lying on the highly oriented pyrolytic graphite surface due to the torsion of the “C”-shaped fused benzene rings. In combination with density functional theory calculation, the selective inclusion of coronene atop the backbone of the PAI1 array might be attributed to the bowl structure, which provides a groove for immobilizing coronene molecules. On the other planar densely packed arrays, it is difficult to observe the unstable adsorption of coronene. The selective addition of coronene molecules would be a strategic step toward the controllable multicomponent supramolecular architectures.Topics: Adsorption; Energy level; Microstructure; Potential energy; Surface structure; Thermodynamic properties; Thin films; Thin films;
Co-reporter:Yanfang Geng;Shouchun Yin;Siqi Zhang;Yongxiang Gong;Chunmei Niu;Qingdao Zeng;Min Li
Langmuir October 27, 2015 Volume 31(Issue 42) pp:11525-11531
Publication Date(Web):2017-2-22
DOI:10.1021/acs.langmuir.5b02883
Formation of an orthogonal supramolecular polymer on a highly oriented pyrolytic graphite (HOPG) surface was demonstrated for the first time by means of scanning probe microscopy (SPM). Atomic force microscopy (AFM) was employed to characterize the variation of both the thickness and the topography of the film formed from (1) monomer 1, (2) monomer 1/Zn2+, and (3) monomer 1/Zn2+/cross-linker 2, respectively. Scanning tunneling microscopy (STM) was used to monitor the self-assembly behavior of monomer 1 itself, as well as 1/Zn2+ ions binary system on graphite surface, further testifying for the formation of linear polymer via coordination interaction at the single molecule level. These results, given by the strong surface characterization tool of SPM, confirm the formation of the orthogonal polymer on the surface of graphite, which has great significance in regard to fabricating a complex superstructure on surfaces.
Co-reporter:Si-Qi Zhang, Zhen-Yu Liu, Wei-Fei Fu, Feng Liu, Chuan-Ming Wang, Chun-Qi Sheng, Yi-Fei Wang, Ke Deng, Qing-Dao Zeng, Li-Jin Shu, Jun-Hua Wan, Hong-Zheng Chen, and Thomas P. Russell
ACS Nano November 28, 2017 Volume 11(Issue 11) pp:11701-11701
Publication Date(Web):November 1, 2017
DOI:10.1021/acsnano.7b06961
Electron-rich (donor) and electron-deficient (acceptor) units to construct donor–acceptor (D–A) conjugated macrocycles were investigated to elucidate their interactions with electron-deficient fullerene. Triphenylamine and 4,7-bisthienyl-2,1,3-benzothiadiazole were alternately linked through acetylene, as the donor and acceptor units, respectively, for pentagonal 3B2A and hexagonal 4B2A macrocycles. As detected by scanning tunneling microscopy, both D–A macrocycles were found to form an interesting concentration-controlled nanoporous monolayer on highly oriented pyrolytic graphite, which could effectively capture fullerene. Significantly, the fullerene filling was cavity-size-dependent with only one C70 or PC71BM molecule accommodated by 3B2A, while two were accommodated by 4B2A. Density functional theory calculations were also utilized to gain insight into the host–guest systems and indicted that the S···π contact is responsible for stabilizing these host–guest systems. Owing to the ellipsoidal shape of C70, C70 molecules are standing or lying in molecular cavities depending on the energy optimization. For the 3B2A/PC71BM blended film, PC71BM was intercalated into the cavity formed by the macrocycle 3B2A and provided excellent power conversion efficiency despite the broad band gap (2.1 eV) of 3B2A. This study of D–A macrocycles incorporating fullerene provides insights into the interaction mechanism and electronic structure in the host–guest complexes. More importantly, this is a representative example using D–A macrocycles as a donor to match with the spherical fullerene acceptor for photovoltaic applications, which offer a good approach to achieve molecular scale p–n junctions for substantially enhanced efficiencies of organic solar cells through replacing linear polymer donors by cyclic conjugated oligomers.Keywords: 2D self-assembly; donor−acceptor; fullerene; host−guest; macrocycles; solar cells;
Co-reporter:Jingfei Hou, Hongliang Dai, Zengqi Zhang, Jun Li, Xiaokang Li, Ke Deng, and Qingdao Zeng
Langmuir 2017 Volume 33(Issue 1) pp:
Publication Date(Web):December 12, 2016
DOI:10.1021/acs.langmuir.6b03567
With the aid of scanning tunneling microscopy, we have examined the two-dimensional hydrogen-bonded networks of carboxyl-functionalized porphyrin derivative H2TCPp molecules at the heptanoic acid/HOPG interface. Moreover, we have successfully modulated the self-assembly structure of H2TCPp by introducing 1,2-di(4-pyridyl)ethylene molecules into the assembled system. By performing density functional theory calculations, we also revealed the formation mechanisms of the different assemblies and the modulation process. Comparing the self-assembly structures at the liquid/solid interface with those in bulk crystals, we have obtained deep insight into the differences in H2TCPp assemblies between 2D and 3D networks. Furthermore, this research is expected to deepen our understanding of on-surface phenomena and to provide a feasible process toward 2D assembly regulation.
Co-reporter:Yanfang Geng;Ping Li;Jindong Xue;Dapeng Luo;Junyong Zhang;Lijin Shu
Nano Research 2017 Volume 10( Issue 3) pp:991-1000
Publication Date(Web):16 December 2016
DOI:10.1007/s12274-016-1358-5
The precise localization of organic molecules in controllable positions is an important step towards constructing functional nanostructures via the bottom-up strategy. Herein, supramolecularly organized C70-fullerene assemblies on macrocycle-modified surfaces were investigated using scanning tunneling microscopy (STM) in combination with theoretical calculations. The results revealed that an up-assembly of C70-fullerene adlayers was successfully formed on top of the bottom macrocycle arrays. Density functional theory (DFT) calculations confirmed that the macrocycle networks along with the co-adsorbed solvent 1-phenyloctane served as a selective template for trapping C70-fullerene molecules in the spectral sites and acted as a support for the C70-fullerene molecules. The periodical distribution of the C70-fullerene molecules should facilitate understanding of the strong dependence of the arrangement of C70-fullerene upon the specific interactions (apart from spatial recognition) derived from modification of the sub-monolayers.
Co-reporter:Hong-Liang Dai, Yan-Fang Geng, Qing-Dao Zeng, Chen Wang
Chinese Chemical Letters 2017 Volume 28, Issue 4(Volume 28, Issue 4) pp:
Publication Date(Web):1 April 2017
DOI:10.1016/j.cclet.2016.09.018
During the past few years, regulation and controlling of the two-dimension (2D) self-assembled supramolecular structure on surface have drawn increasing attention in nanoscience and technology. External stimuli have been widely used to regulate these 2D nanostructures. Among various external stimuli approaches, photo-regulation as one of the most outstanding means of regulation has been extensively studied because different wave bands can lead to molecular conformation variation and new bonds to gain new molecules. In this review, the photo-regulated self-assembled structure on solid surface as well as the photo-reactions of different molecules substituted with photo-sensitive groups are introduced to give us an insight into on-surface photochemistry, which plays an important role on the nano-devices fabrication. Notably, these photo-sensitive behaviors as well as the formed structures on surface were probed at sub-molecule level by unique scanning tunneling microscopy (STM) technique.Download high-res image (126KB)Download full-size imageThis review summarizes the recent progress on self-assemblies and reactions of molecules with different photo-sensitive groups upon photo-irradiation on solid surface probed by scanning tunneling microscopy (STM) technique.
Co-reporter:Jing Xu;Wenxu Liu;Yanfang Geng;Ke Deng;Chuanlang Zhan;Qingdao Zeng
Nanoscale (2009-Present) 2017 vol. 9(Issue 7) pp:2579-2584
Publication Date(Web):2017/02/16
DOI:10.1039/C6NR08234C
In this article, a donor–acceptor H-T-BO/C70 system was studied by a STM/STS method on the molecular level. STM results revealed that H-T-BO, a BODIPY-based derivative, can form a semi-closed molecular network at the 1-phenyloctane/HOPG interface. After introducing C70 fullerene molecules into the network, two kinds of self-assembled nanoarrays were observed by STM. Density functional theory has been utilized to reveal the formation mechanism of the molecular nanoarrays. Scanning Tunneling Spectroscopy (STS) measurements were performed to investigate the electronic properties of H-T-BO/C70 systems. I–V spectra combined with theoretical analyses showed that the introduction of C70 into the H-T-BO system induced a great drop of the band gap, which should be a result of electrons transferring from the donor H-T-BO to the acceptor C70 molecules.
Co-reporter:Mengqi Shen, Zhouyang Luo, Siqi Zhang, Shuai Wang, Lili Cao, Yanfang Geng, Ke Deng, Dahui Zhao, Wubiao Duan and Qingdao Zeng
Nanoscale 2016 vol. 8(Issue 23) pp:11962-11968
Publication Date(Web):17 May 2016
DOI:10.1039/C6NR02269C
In the present investigation, we reported the fabrication of host networks formed by two newly prepared phenanthrene-butadiynylene macrocycles (PBMs) at the liquid–solid interface. Size, shape and concentration controlled experiments have been performed to investigate the PBMs/coronene (COR) host–guest system with the structural polymorphism phenomenon. Initially, PBM1 could form a regular linear network structure and PBM2 form a well-ordered nanoporous network structure. When the COR molecules were introduced, the self-assembled structure of PBM1 remained unchanged, while COR could be entrapped into the cavities of the PBM2 nanoporous network, and the co-assembly of the PBM2/COR host–guest systems underwent a structural transformation with the increase of concentration of COR. Scanning tunneling microscopy (STM) measurements and density functional theory (DFT) calculations are utilized to reveal the formation mechanism of the molecular nanoarrays controlled by the solution concentration.
Co-reporter:Jing Xu, Xunwen Xiao, Ke Deng and Qingdao Zeng
Nanoscale 2016 vol. 8(Issue 3) pp:1652-1657
Publication Date(Web):10 Dec 2015
DOI:10.1039/C5NR07345F
The self-assembly of a tetrathiafulvalene (TTF) derivative (EDTTF) and a 1,3,5-tris(10-carboxydecyloxy)-benzene (TCDB) heterobilayer nanostructure at the 1-phenyloctane/HOPG interface under ambient conditions has been studied by scanning tunneling microscopy (STM). EDTTF and TCDB could co-assemble into a brand new hexagonal network with one of the largest nano-cavities. Finally, the nanoporous network would transform into a more stable linear structure. Density functional theory (DFT) calculations have been performed to reveal the formation mechanism.
Co-reporter:Hongliang Dai, Wenjing Yi, Ke Deng, Hua Wang, and Qingdao Zeng
ACS Applied Materials & Interfaces 2016 Volume 8(Issue 32) pp:21095
Publication Date(Web):July 27, 2016
DOI:10.1021/acsami.6b06638
In this research, with the assistance of scanning tunneling microscopy (STM), we observed the two-dimensional (2D) self-assembly transition of a star-shaped oligofluorene derivative (StOF) from disordered structure to honeycomb network by adjusting StOF concentration in solution. By introducing guest molecules coronene (COR), we for the first time achieved novel triangle-shaped COR trimers on liquid/highly oriented pyrolytic graphite (HOPG) interface in both honeycomb network and the disordered structure. In thermal tests, the COR/StOF–disorder system underwent a structural conformation to form well-ordered ladder structures, while the COR/StOF–honeycomb system remained the perfect hexagonal network with COR trimers included in the cavities. Density functional theory (DFT) calculations have been employed to investigate the forming mechanism of the molecular nanoarrays. These studies are expected to enhance controlling on 2D self-assembly and provide a facial approach toward constructing on-surface molecular clusters.Keywords: concentration regulation; coronene cluster; honeycomb network; scanning tunneling microscopy; temperature regulation
Co-reporter:Linxiu Cheng, Yibao Li, Chun-Yu Zhang, Zhong-Liang Gong, Qiaojun Fang, Yu-Wu Zhong, Bin Tu, Qingdao Zeng, and Chen Wang
ACS Applied Materials & Interfaces 2016 Volume 8(Issue 46) pp:32004
Publication Date(Web):November 1, 2016
DOI:10.1021/acsami.6b10883
Temperature triggered chiral nanostructures have been investigated on two-dimensional (2D) surfaces by means of scanning tunneling microscopy. Achiral molecules 1 and 2 tend to self-assemble into strip structures on graphite before heating. However, R and S flower-like structures are observed when heated to certain temperature. The transition temperatures of 1 and 2 systems are 55 and 60 °C, respectively. The density functional theory calculations demonstrate that R and S flower-like structures are more stable than strip structures. The coexistence of flower-like structures and strip structures demonstrates the thermodynamic equilibrium. Further, when chiral solvent is added to the sample with other conditions remaining the same, the racemic phenomenon disappears and homochirality emerges. This is an efficient method to control the chirality of 2D molecular assemblies.Keywords: achiral molecules; chiral self-assembly; flower-like structure; scanning tunneling microscopy; temperature-triggered
Co-reporter:Junyong Zhang, Shaoqing Chang, Bryan H. R. Suryanto, Chunhua Gong, Xianghua Zeng, Chuan Zhao, Qingdao Zeng, and Jingli Xie
Inorganic Chemistry 2016 Volume 55(Issue 11) pp:5585-5591
Publication Date(Web):May 10, 2016
DOI:10.1021/acs.inorgchem.6b00670
Taking advantage of a continuous-flow apparatus, the iridium(III)-containing polytungstate cluster K12Na2H2[Ir2Cl8P2W20O72]·37H2O (1) was obtained in a reasonable yield (13% based on IrCl3·H2O). Compound 1 was characterized by Fourier transform IR, UV–visible, 31P NMR, electrospray ionization mass spectrometry (ESI-MS), and thermogravimetric analysis measurements. 31P NMR, ESI-MS, and elemental analysis all indicated 1 was a new polytungstate cluster compared with the reported K14[(IrCl4)KP2W20O72] compound. Intriguingly, the successful isolation of 1 relied on the custom-built flow apparatus, demonstrating the uniqueness of continuous-flow chemistry to achieve crystalline materials. The catalytic properties of 1 were assessed by investigating the activity on catalyzing the electro-oxidation of ruthenium tris-2,2′-bipyridine [Ru(bpy)3]2+/3+. The voltammetric behavior suggested a coupled catalytic behavior between [Ru(bpy)3]3+/2+ and 1. Furthermore, on the highly oriented pyrolytic graphite surface, 1,3,5-tris(10-carboxydecyloxy) benzene (TCDB) was used as the two-dimensional host network to coassemble cluster 1; the surface morphology was observed by scanning tunneling microscope technique. “S”-shape of 1 was observed, indicating that the cluster could be accommodated in the cavity formed by two TCDB host molecules, leading to a TCDB/cluster binary structure.
Co-reporter:Yan-Fang Geng, Shi-Li Wu, Jing Xu, Hong-Liang Dai, Xiao-Kang Li, Ke Deng, Qing-Dao Zeng
Chinese Chemical Letters 2016 Volume 27(Issue 4) pp:602-606
Publication Date(Web):April 2016
DOI:10.1016/j.cclet.2016.01.033
The formation of coordinated dimeric complexes bridged by axial ligands on surface is observed with the help of a 1,3,5-tris(10-carboxydecyloxy)benzene (TCDB) template through scanning tunneling microscopy (STM). STM images of molecular adlayers of zinc tetraphenylporphyrin (ZnTPP), zinc phthalocyanine (ZnPc), and their mixture are reported. ZnTPP and ZnPc can spontaneously form highly an ordered structure with a 1:1 molar ratio, which is different from that of individual ZnPc. The coordinated bimolecular complexes bridged with axial ligands, simply as ZnPc–DPP–ZnTPP and ZnPc–DPE–ZnPc, are presented and the corresponding surface structures are compared. ZnPc and ZnTPP can be connected by an axial ligand DPP and formed assembled structures out of surface. Two types of arrays with entirely new structure are obtained for the ZnPc–DPE–ZnPc complex. These bridged hybrid complexes provide an example of design of self-organized crystals on the basis of coordination through non-covalent interactions.We have observed heterocaryotic and homonuclear dimeric complexes of ZnTPP–ZnPc and ZnPc–ZnPc bridged by axial ligands DPP and DPE in a template of TCDB on HOPG surface by means of scanning tunneling microscopy (STM).
Co-reporter:Lixin Cai, Liancheng Wang, Shizhao Kang, Yanfang Geng, Ke Deng, Qiyu Zheng, and Qingdao Zeng
The Journal of Physical Chemistry C 2016 Volume 120(Issue 48) pp:27259-27267
Publication Date(Web):November 17, 2016
DOI:10.1021/acs.jpcc.6b06605
Functional molecules, especially with carboxyl groups are crucial in building supramolecular structures. It is great important to study the effect of the symmetry, number of carboxyl groups on the self-assembly behavior of corresponding molecules. A series of hexaphenylbenzene (HPB) derivatives (HPB-1,3,5-3A, HPB-1,2,4-3A, and HPB-1,4-2A) substituted with different number of carboxyl groups at different position have been synthesized and their self-assembled structures were investigated at both 1-phenyloctane/HOPG and heptanoic acid/HOPG interfaces by using scanning tunneling microscopy (STM) technique. The self-assembled mechanisms of these HPB-based compounds were further studied with the help of density functional theory (DFT) calculations. The results indicate that symmetry and number of carboxyl groups as well as solvent play a significant role on the tuning self-assemble process resulting in various structures.
Co-reporter:Shaoqing Chang, Runcong Liu, Liancheng Wang, Min Li, Ke Deng, Qiyu Zheng, and Qingdao Zeng
ACS Nano 2016 Volume 10(Issue 1) pp:342
Publication Date(Web):December 9, 2015
DOI:10.1021/acsnano.5b06666
In the present work, we report the fabrication of regular coronene (COR) clusters on surfaces in ambient conditions in the two-dimensional network formed by hexaphenylbenzene derivatives (HPB) via structural transformation. HPB could form a stable snowflake network structure on the highly oriented pyrolytic graphite surface at the air–solid interface. When COR molecules were introduced into the system, the HPB snowflake network could transform to honeycomb structures, and the COR heptamers were subsequently aggregated and entrapped into the cavity. Scanning tunneling microscopic was employed to monitor the assembly behavior of both HPB and HPB/COR at a submolecule scale level, and density functional theory calculations were utilized to reveal that the structural transformation and the entrapment are the energetically favorable. The pores formed from HPB might also give a clue to immobilizing some functional molecule clusters, like COR, to fabricate their ordered monolayer in ambient conditions, so as to obtain complex supramolecular surface structures.Keywords: coronene cluster; guest inclusion; HPB network; scanning tunneling microscopy; structural transformation;
Co-reporter:Shili Wu
The Journal of Physical Chemistry C 2016 Volume 120(Issue 23) pp:12618-12625
Publication Date(Web):May 18, 2016
DOI:10.1021/acs.jpcc.6b03660
Self-assemblies of two newly designed pairs of hexylaniline derivatives connected with diynes (4J and 4JT2, 6J and 6JT2) at heptanoic acid/highly oriented pyrolytic graphite interface under ambient conditions have been studied by scanning tunneling microscopy. The functionalized π-conjugated molecules and solvent (heptanoic acid) were detected to co-assemble into different ordered networks. Density functional theory calculations were utilized to reveal the formation mechanisms of these nanoarrays and verify the synergism of van der Waals interactions and various hydrogen-bonding interactions in the self-assemblies.
Co-reporter:Yanfang Geng, Miaoqing Liu, Jindong Xue, Peng Xu, Yifei Wang, Lijin Shu, Qingdao Zeng and Chen Wang
Chemical Communications 2015 vol. 51(Issue 31) pp:6820-6823
Publication Date(Web):12 Mar 2015
DOI:10.1039/C5CC01032B
An amine-substituted macrocycle 6Y, a rigid hexagonal ring, self-assembled into network architecture on the surface, which could be used as a molecular template to directly fabricate gold nanoparticles (AuNPs) with narrow size distribution (2.2 ± 0.1 nm). This work demonstrated a new pathway for the formation of controllable AuNPs on the surface.
Co-reporter:Yanfang Geng, Hongliang Dai, Shaoqing Chang, Fangyun Hu, Qingdao Zeng, and Chen Wang
ACS Applied Materials & Interfaces 2015 Volume 7(Issue 8) pp:4659
Publication Date(Web):February 9, 2015
DOI:10.1021/am508068m
Controlling chemical reactions on surface is of great importance to constructing self-assembled covalent nanostructures. Herein, Knoevenagel reaction between aromatic aldehyde compound 2,5-di(5-aldehyde-2-thienyl)-1,4-dioctyloxybenzene (PT2) and barbituric acid (BA) has been successfully performed for the first time at liquid/HOPG interface and vapor/HOPG interface. The resulting surface nanostructures and the formation of C═C bond are recorded through scanning tunneling microscopy (STM), and confirmed by attenuated total reflectance Fourier-transform infrared (ATR/FT-IR) spectrometer and UV–vis absorption. The obtained results reveal that Knoevenagel condensation reaction can efficiently occur at both interfaces. This surface reaction would be an important step toward further reaction to produce innovative conjugated nanomaterial on the surface.Keywords: C═C bond; interface; Knoevenagel reaction
Co-reporter:Siqi Zhang, Junyong Zhang, Ke Deng, Jingli Xie, Wubiao Duan and Qingdao Zeng
Physical Chemistry Chemical Physics 2015 vol. 17(Issue 37) pp:24462-24467
Publication Date(Web):24 Aug 2015
DOI:10.1039/C5CP04065E
In the present investigation, we reported the fabrication of a chicken-wire porous 2D network formed by triphenylene-2,6,10-tricarboxylic acid (H3TTCA) at the liquid–solid interface. When coronene (COR) molecules were added into the system, the H3TTCA honey-comb network was broken and the reconstructed structures of the H3TTCA/COR host–guest systems were subsequently formed. Scanning tunneling microscopic (STM) measurements and density function theory (DFT) calculations were utilized to reveal the structural variety in the co-assembly of H3TTCA/COR controlled by the solution concentration at 1-heptanoic acid/HOPG interface.
Co-reporter:Shuai Wang, Fengying Zhao, Shiwen Luo, Yanfang Geng, Qingdao Zeng and Chen Wang
Physical Chemistry Chemical Physics 2015 vol. 17(Issue 18) pp:12350-12355
Publication Date(Web):09 Apr 2015
DOI:10.1039/C5CP00531K
Variable supramolecular structures constructed by bis-(2,2′:6′,2′′-terpyridine)-4′-oxyhexadecane (BT-O-C16) on a highly oriented pyrolytic graphite (HOPG) surface were investigated by scanning tunneling microscopy (STM). Seven different solvents (1-phenyloctane, n-tetradecane, n-dodecane, n-decane, n-octane, 1-heptanoic acid, and 1-octanoic acid) were utilized to affect the self-assembling structures of BT-O-C16 at liquid/HOPG interfaces. High-resolution STM analyses revealed that various nanostructures were formed by the change of molecular conformation, which are actually driven by the cooperative interaction effect under different environments. Therefore, the solvent-induced cooperative influence on the molecular self-assembly is important for constructing supramolecular nanostructures.
Co-reporter:Xianghua Zeng, Shaoqing Chang, Ke Deng, Junyong Zhang, Hongbin Sun, Qingdao Zeng, and Jingli Xie
Crystal Growth & Design 2015 Volume 15(Issue 7) pp:3096
Publication Date(Web):June 8, 2015
DOI:10.1021/acs.cgd.5b00143
Three new (R)-BINOL complexes have been prepared. 2D self-assembly has been observed in the system consisting of crystalline (R)-BINOL derivatives (guest) and 1,3,5-tris(10-carboxydecyloxy)-benzene (host) by means of the scanning tunneling microscopy (STM) technique. Density functional theory (DFT) calculations help to reveal the assembly on the HOPG surface.
Co-reporter:JinDong Xue, Ke Deng, Bo Liu, WuBiao Duan, QingDao Zeng and Chen Wang
RSC Advances 2015 vol. 5(Issue 49) pp:39291-39294
Publication Date(Web):21 Apr 2015
DOI:10.1039/C5RA01517K
In the present investigation, we report the fabrication of a flexible binary network formed by tetraacidic azobenzene (NN4A) and trans-1,2-bis(4-pyridyl)ethylene (DPE) at the liquid–solid interface. When coronene (COR) molecule is added into these systems, the binary networks break and the reconstruction structures of NN4A/COR host–guest systems are subsequently formed. Scanning tunneling microscopy (STM) measurements, as well as density functional theory (DFT) calculations, reveal that the NN4A/COR host–guest system is the energetically favourable structure and with the most thermodynamic stability. These studies give us insight into a better comprehension of competitive adsorption for the fabrication of functional molecular assemblies.
Co-reporter:Hui Nie;Yanfang Geng;Dapeng Luo;Miaoqing Liu;Yifei Wang;Zhenyu Liu;Dr. Qingdao Zeng;Dr. Lijin Shu
Asian Journal of Organic Chemistry 2015 Volume 4( Issue 8) pp:788-793
Publication Date(Web):
DOI:10.1002/ajoc.201500146
Abstract
A shape-persistent macrocycle consisting of 2,6-disubstituted aniline linked by acetylene, butadiyne, and an inner tetraethylene glycol bridge was prepared by Pd/Cu homocoupling oxidation reaction. The morphology of the resulting macrocycle was demonstrated and discussed, indicating the establishment of channels with amine functional groups inside the pores. Polarized optical microscopy (POM) observation of the macrocycle indicated the formation of liquid crystals (LCs) in the heating and cooling processes.
Co-reporter:Jing Xu ;Qingdao Zeng
Chinese Journal of Chemistry 2015 Volume 33( Issue 1) pp:53-58
Publication Date(Web):
DOI:10.1002/cjoc.201400499
Abstract
In this review, supramolecular coordination processes on two-dimensional (2D) surfaces or interfaces observed by scanning tunneling microscopy (STM) are discussed. Four parts are mainly involved, which include (1) recognition of Fe3+ through functional molecular networks, (2) K+-induced switching of valinomycin, (3) supramolecular coordination happened in a nano-reactor, (4) reversible 2D supramolecular spring driven by coordination. The direct insight of the coordination phenomena provided by STM supplements our knowledge of its mechanism. Since different building blocks can be connected into a whole part through coordination, the understanding of its mechanism will be beneficial to the future design of molecular devices.
Co-reporter:Yanfang Geng, Jing Xu, Jindong Xue, Xiaomin Shen, Min Li, Jiandong Huang, Xiaokang Li, and Qingdao Zeng
Langmuir 2015 Volume 31(Issue 49) pp:13394-13401
Publication Date(Web):November 24, 2015
DOI:10.1021/acs.langmuir.5b03690
Molecular conformation is an important issue related to the self-assembly architecture and property. The self-assembly of silicon(IV) phthalocyanines covalently linked to the 5-N-cytidine or 4-carboxyphenoxy moiety at the axial positions, namely, SiPc(NC)2 and SiPc(CP)2, respectively, has been studied by means of scanning tunneling microscopy (STM) at the solid–liquid interface. The intermolecular axial hydrogen bonding in combination with the stabilizing role of the TCDB template brings about supramolecular self-assembled structures of silicon(IV) phthalocyanines in an edge-on orientation. Two pyridine compounds, 4,4′-bipyridine (BPY) and 1,2-di(4-pyridyl)ethylene (DPE), can tune the supramolecular structure, leading to interestingly axial self-assemblies of SiPc(CP)2 with BPY and DPE in an edge-on manner by hydrogen bonding. The results indicate that the axial substituents and the axial ligands can regulate and precisely control the conformation and arrangement of the phthalocyanine moiety on the graphite surface.
Co-reporter:Jing Xu
The Journal of Physical Chemistry C 2015 Volume 119(Issue 17) pp:9227-9233
Publication Date(Web):April 8, 2015
DOI:10.1021/jp512079z
In this investigation, we reported the two-dimensional (2D) self-assembly of a pair of triangular macrocycles (TMC1 and TMC2) at a highly oriented pyrolytic graphite (HOPG)/1-phenyloctane interface. Although with the similar triangle-shaped phenyl backbones, TMC1 and TMC2 displayed different 2D nanopatterns. Control experiments with varying concentrations and temperatures have been carried out. Phase separations were recorded in the coassembly of TMC1 and TMC2. Scanning tunneling microscopy (STM) measurements, as well as density function theory (DFT) calculations, revealed the formation mechanism of the TMC1 and TMC2 nanoarrays. Moreover, minor ring-opening phenomena of TMC2 were detected by STM, which demonstrates the advantages of STM in trace content analysis.
Co-reporter:Yanfang Geng
The Journal of Physical Chemistry C 2015 Volume 119(Issue 32) pp:18216-18220
Publication Date(Web):July 16, 2015
DOI:10.1021/acs.jpcc.5b03878
The morphology of self-assembled monolayers determined by molecular structure and involved interactions plays a crucial role in their properties. Herein, we report a study on 2D self-assembly of two kinds of triphenylene-submitted discotic mesogenic species, which have similar four TP moieties with alkyne spacer but different rigid aromatic cores pyrene and carbazole. Two types of stable periodic long-ranged supramolecular networks on the highly oriented pyrolytic graphite surface have been visualized via high-resolution scanning tunneling microscopy technique. A comparative study reveals how the aromatic core of molecular building blocks affects achiral and chiral arrangement of discotic molecule on surface. The asymmetry backbone results in molecular orientation and varied van der Waals forces between molecule–molecule and molecule–substrate. Our results demonstrate that design of functional molecules plays an important role in the construction of 2D supramolecular assembly possessing desirable structure for the specific applications.
Co-reporter:Yongtao Shen, Ke Deng, Songlin Yang, Bo Qin, Shiyu Cheng, Ningbo Zhu, Jiejin Ding, Dahui Zhao, Ji Liu, Qingdao Zeng and Chen Wang
Nanoscale 2014 vol. 6(Issue 13) pp:7221-7225
Publication Date(Web):05 May 2014
DOI:10.1039/C4NR01595A
Macrocycle-1 molecules can self-assemble into glassy state networks via van der Waals force and form many triangular nanopores in networks. The nanopores can be expressed by triangular tilings, which lead to a particularly rich range of arrangements. Moreover an interesting molecular rotation phenomenon was observed in the glassy networks.
Co-reporter:Fangyun Hu, Yunnan Gong, Xuemei Zhang, Jindong Xue, Bo Liu, Tongbu Lu, Ke Deng, Wubiao Duan, Qingdao Zeng and Chen Wang
Nanoscale 2014 vol. 6(Issue 8) pp:4243-4249
Publication Date(Web):28 Jan 2014
DOI:10.1039/C3NR06320H
A promising approach to create functional nanoarrays is supramolecular self-assembly at liquid–solid interfaces. In the present investigation, we report on the self-assembly of phthalocyanine arrays using triphenylene-2,6,10-tricarboxylic acid (H3TTCA) as a molecular nanotemplate. Five different metastable arrays are achieved in the study, including a thermodynamically stable configuration. Scanning tunneling microscopy (STM) measurements and density function theory (DFT) calculations are utilized to reveal the formation mechanism of the molecular nanoarrays. In general, the transformation process of nanoarrays is regulated by the synergies of a template effect and thermodynamic balance.
Co-reporter:Dapeng Luo, Xuemei Zhang, Yongtao Shen, Jing Xu, Lijin Shu, Qingdao Zeng and Chen Wang
Chemical Communications 2014 vol. 50(Issue 66) pp:9369-9371
Publication Date(Web):20 Jun 2014
DOI:10.1039/C4CC02120G
A tetraethylene glycol ether bridged derivative 9 has been designed and synthesized, and its two-dimensional (2D) self-assembled behavior has been investigated at the single-molecule level. Our results revealed that 9 generally adopted the fully extended state but changed to the contracted state when triggered by K2CO3, and recovered the original fully extended conformation after subsequent addition of 18-crown-6. Such a coordination-controlled reversible assembly reveals supramolecular springs in response to chemical stimuli, which is of great interest in bionics and materials science.
Co-reporter:JinDong Xue, Jing Xu, FangYun Hu, LingYan Liao, Min Li, WuBiao Duan, QingDao Zeng and Chen Wang
Physical Chemistry Chemical Physics 2014 vol. 16(Issue 47) pp:25765-25769
Publication Date(Web):21 Oct 2014
DOI:10.1039/C4CP04154B
Efficient photochemical reactions on a surface are of great importance for their potential applications in optoelectronic devices. In this work, a highly efficient photodimerization reaction of an olefin cocrystal built from two trans-1,2-bis(4-pyridyl)ethylenes (4,4′-bpe) and two isophthalic acid molecules via N⋯H–O hydrogen bonds in between was achieved in a nanotemplate on a highly oriented pyrolytic graphite (HOPG) surface. 4,4′-Bpe molecules first undergo the trans–cis isomerization followed by [2+2] photodimerization in the nanotemplate on HOPG upon UV irradiation. The efficiency of the isomerization as well as the photodimerization in the presence of the nanotemplate is much higher than that in its absence. These results provide a facile way to achieve highly efficient photodimerization of olefins on a large scale on surfaces.
Co-reporter:Min Li, Peng Xie, Ke Deng, Yan-Lian Yang, Sheng-Bin Lei, Zhong-Qing Wei, Qing-Dao Zeng and Chen Wang
Physical Chemistry Chemical Physics 2014 vol. 16(Issue 19) pp:8778-8782
Publication Date(Web):18 Mar 2014
DOI:10.1039/C3CP55355H
In the present work flexible binary networks of 1,3,5-benzenetricarboxylic acid (TMA) with 4,4′-bipyridine (Bpy) or 1,3,5-tris(4-pyridyl)-2,4,6-triazine(TPTZ) molecules at the liquid–solid interface were constructed. When coronene (COR) molecules are introduced into these systems, the binary networks collapse and at the same time, new COR/TMA host–guest structures are formed. Both experiments and calculations unambiguously indicate that the COR/TMA host–guest complex structure has stronger adsorption energy, resulting in the deconstruction–reconstruction phenomenon.
Co-reporter:Ling-yan Liao ; Xue-mei Zhang ; Fang-yun Hu ; Shuai Wang ; Shan-Dong Xu ; Qing-dao Zeng ;Chen Wang
The Journal of Physical Chemistry C 2014 Volume 118(Issue 15) pp:7989-7995
Publication Date(Web):March 25, 2014
DOI:10.1021/jp412793w
In this paper, four stilbene derivatives substituted with ester groups were synthesized and their two-dimensional (2D) self-assembled behaviors were investigated by scanning tunneling microscopy (STM) on the highly oriented pyrolytic graphite (HOPG) surface. The four target molecules are different in the symmetrical properties and the length of substituted alkoxy chains which extremely influence the self-assembly of these molecules on graphite surface. As a result, we obtained four kinds of nanostructures including chiral supramolecular networks and linear lamellae, as probed at a single molecule level.
Co-reporter:Ling-yan Liao ; Yi-bao Li ; Xue-mei Zhang ; Yan-fang Geng ; Jun-yong Zhang ; Jing-li Xie ; Qing-dao Zeng ;Chen Wang
The Journal of Physical Chemistry C 2014 Volume 118(Issue 29) pp:15963-15969
Publication Date(Web):July 7, 2014
DOI:10.1021/jp505511e
The photochemical reactions of stilbene and its derivatives have been extensively investigated in the gas and liquid phases but less on surfaces. In this work, scanning tunneling microscopy (STM) has been employed to investigate the photoisomerization and photodimerization of two stilbene derivatives on HOPG surface. After UV-light irradiation, one stilbene derivative performs photoinduced trans to cis isomerization and a well-ordered Kagomé network with two types of cavities forms at the 1-phenyloctane/HOPG interface, which is totally different from the lamella structures (before irradiation). Another stilbene derivative can also perform trans to cis photoreaction and the assembly structures have two conformations. With the increase of the irradiation time, one of the two conformations according to the topochemical postulates can further perform [2 + 2] photodimerization reaction. The difference in alkoxy substitution is reflected in the self-assembled monolayer and consequently also in the photoreactivity.
Co-reporter:Ling-yan Liao ; Yi-bao Li ; Jing Xu ; Yan-fang Geng ; Jun-yong Zhang ; Jing-li Xie ; Qing-dao Zeng ;Chen Wang
The Journal of Physical Chemistry C 2014 Volume 118(Issue 49) pp:28625-28630
Publication Date(Web):November 20, 2014
DOI:10.1021/jp509041b
The molecule–molecule and molecule–substrate interactions play an important role during the formation of two-dimensional (2D) supramolecular nanostructure. In this paper, the self-assembled monolayers of four stilbene derivatives possessing different chemical structures at the liquid–solid interface were investigated by employing scanning tunneling microscopy (STM). Chemical structures that affect the 2D molecular self-assembly, such as number of alkoxyl chain with carboxylic acid end-group and length of alkoxyl chain, were elucidated in detail. Systematic investigation indicated that various self-assembly structures consequently formed on highly oriented pyrolytic graphite (HOPG) surface, via a combination of intermolecular hydrogen bonding and van der Waals interactions. It is proposed that hydrogen bonding and van der Waals interactions competitively control the morphology of the monolayer, and the self-assembled 2D nanostructure is determined by balance of these two interactions.
Co-reporter:XueMei Zhang;QingDao Zeng;Chen Wang
Science China Chemistry 2014 Volume 57( Issue 1) pp:13-25
Publication Date(Web):2014 January
DOI:10.1007/s11426-013-4975-9
Supramolecular self-assembly, an important strategy in nanotechnology, has been widely studied in the past two decades. In this review, we have introduced the recent progress on construction of two-dimensional (2D) nanostructures by host-guest supramolecular chemistry at solid-liquid interface, and the interactions between the host assembly and the guest molecules are the major concerns. At first, the hydrogen bonds connected hybrid structures are discussed. And then we have paid a close attention on the surface-confined condensation reactions that has flourished recently in direct preparing novel nanostructures with increasing structural complexity. In the end, the cavity confinement of the 2D supramolecular host-guest architectures has been studied. On the basis of the above-mentioned interactions, a group of functional hybrid structures have been prepared. Notably, scanning tunneling microscopy (STM), a unique technique to probe the surface morphology and information at the single molecule level, has been used to probe the formed structures on highly oriented pyrolytic graphite (HOPG) surface.
Co-reporter:Xuemei Zhang, Qingdao Zeng and Chen Wang
Nanoscale 2013 vol. 5(Issue 18) pp:8269-8287
Publication Date(Web):07 May 2013
DOI:10.1039/C3NR01611K
In this review, we introduce recent progress on surface synthesis and focus on supramolecular self-assembled structures driven by several typical chemical reactions at solid surfaces, with the aid of scanning tunneling microscopy (STM). We also emphasize the relationship between the non-covalent self-assembly and surface reactivity, by which we hope to find an effective way for further controllable nano-manufacture.
Co-reporter:Fang-Yun Hu, Xue-Mei Zhang, Xiao-Chen Wang, Shuai Wang, Hai-Qiao Wang, Wu-Biao Duan, Qing-Dao Zeng, and Chen Wang
ACS Applied Materials & Interfaces 2013 Volume 5(Issue 5) pp:1583
Publication Date(Web):February 4, 2013
DOI:10.1021/am303236w
Nanoscaled two-dimensional (2D) chiral architectures are increasingly receiving scientific interest, because of their potential applications in many domains. In this paper, we present a new method for constructing 2D chiral architectures on surface. Based on in situ Schiff-base reaction of achiral dialdehyde with two types of achiral amines at the solid/liquid interface, two chiral species have been directly formed and confirmed by means of a scanning tunneling microscopy (STM) technique. This work introduces a novel strategy to construct 2D surface chirality, which might be applied in fabricating functional films and nanoelectronic devices.Keywords: chirality; nanoflower; Schiff-base reaction; self-assembly; STM; two-dimensional;
Co-reporter:Yibao Li, Chunhua Liu, Yunzhi Xie, Xun Li, Xiaolin Fan, Lihua Yuan and Qingdao Zeng
Chemical Communications 2013 vol. 49(Issue 79) pp:9021-9023
Publication Date(Web):09 Aug 2013
DOI:10.1039/C3CC44978E
The K+-induced switching of valinomycin has been studied using a molecular template formed by an aromatic oligoamide macrocycle at the liquid/solid interface by scanning tunneling microscopy (STM). Individual valinomycin and its K+ complex can be identified and resolved in the molecular template, and the high-resolution STM images of valinomycin and its K+ complex show triangle-like and cyclic structural characteristics, respectively.
Co-reporter:Yongtao Shen, Ke Deng, Min Li, Xuemei Zhang, Gang Zhou, Klaus Müllen, Qingdao Zeng and Chen Wang
CrystEngComm 2013 vol. 15(Issue 27) pp:5526-5531
Publication Date(Web):09 May 2013
DOI:10.1039/C3CE40340H
5,10,15,20-Tetrakis(4-tetradecylphenyl)-porphyrin (P14) has been synthesized and its self-assembling behavior on highly oriented pyrolytic graphite (HOPG) surfaces when coadsorbing with tetradecane molecules have been investigated in this work. Scanning tunneling microscope (STM) studies show that the phthalocyanine (Pc) and copper(II) 1,2,3,4,8,9,10,11,15,16,17,18,22,23,24,25-hexadecafluoro-29H,31H-phthalocyanine (F16CuPc) can be immobilized by the network formed from P14 and consequently lead to two kinds of well-defined hybrid porphyrins and phthalocyanines hybrid nano-arrays. Interestingly, F16CuPc could form multilayer structure. The theoretical simulation results show that π–π stacking interactions and C–H⋯F–C hydrogen bonding between P14 and F16CuPc play a major role in stabilizing the P14/F16CuPc alternating single-/multi-layer architecture.
Co-reporter:Xuemei Zhang, Haijun Xu, Yongtao Shen, Yibing Wang, Zhen Shen, Qingdao Zeng and Chen Wang
Physical Chemistry Chemical Physics 2013 vol. 15(Issue 30) pp:12510-12515
Publication Date(Web):14 May 2013
DOI:10.1039/C3CP51586A
In this paper, a novel core-modified porphyrin with meso-aryl substituents and phenanthrene-fused pyrrole rings (N2S2–OR) is synthesized. Scanning tunneling microscopy (STM) has been used to probe its self-assembly behavior on a highly-oriented pyrolytic graphite (HOPG) surface. Our STM results have shown that there is an obvious solvent-dependent self-assembly for the surface-confined target molecules. In n-tetradecane, N2S2–OR assembles into a perfect alternating structure. At the 1-phenyloctane–graphite interface, disordered structures are formed and nonperiodic alternation is observed, whereas the target molecule in 1-heptanoic acid is assumed to form homogeneous close-packed monolayers with no alternating. Interestingly, such solvent-dependent supramolecular assembled behavior also involves the structural transformation of the backbone of the core-modified porphyrin derivative from saddle to reversed-saddle in these three solvents with different polarities.
Co-reporter:Yong-Tao Shen, Li Guan, Xue-Mei Zhang, Shuai Wang, Li-Hua Gan, Qing-Dao Zeng and Chen Wang
Physical Chemistry Chemical Physics 2013 vol. 15(Issue 30) pp:12475-12479
Publication Date(Web):28 Mar 2013
DOI:10.1039/C3CP50371B
2D porous networks have attracted great attention as they can be used to immobilize functional units as guest molecules in a spatially ordered arrangement. In this work, a novel molecular hybrid network with two kinds of cavities was fabricated. Several kinds of guest molecules, such as coronene, copper(II) phthalocyanine (CuPc), triphenylene, heptanoic acid and fullerene molecules, can be immobilized into this template. Site- and size-selective effects can be observed. Furthermore, we have also fabricated interesting 2D crystal architecture with complex four-component structure at the liquid–solid interface, following investigation by scanning tunnelling microscopy (STM). The current findings provide a convenient approach towards the formation of more complex and functionalized surface nanopatterns, which can benefit the study of host–guest assembly behaviour within a monolayer composed by several components at interfaces.
Co-reporter:Yibao Li, Chunhua Liu, Yunzhi Xie, Xiaokang Li, Xun Li, Xiaolin Fan, Ke Deng, Qingdao Zeng and Chen Wang
Physical Chemistry Chemical Physics 2013 vol. 15(Issue 1) pp:125-128
Publication Date(Web):24 Oct 2012
DOI:10.1039/C2CP43244G
We investigate the influence of temperature on the self-assembly of 2,6,11-tricarboxydecyloxy-3,7,10-triundecyloxy triphenylene (asym-TTT) adsorbed on HOPG using scanning tunneling microscopy (STM) at the liquid/solid interface. We show that the packing structures of 2D self-assembled asym-TTT can be precisely tuned by adjusting the substrate temperature. The temperature change from 20 °C to 35 °C induces two phase transitions and increment in the packing density from 0.161 to 0.179 molecules per nm2. The density-functional theory (DFT) calculations reveal that their interaction energies are similar. In particular, the experimental findings further illustrate the preferential adsorption of guest molecules, such as phthalocyanine, only in the domain of more close packing structures.
Co-reporter:Xuemei Zhang, Qingdao Zeng and Chen Wang
RSC Advances 2013 vol. 3(Issue 29) pp:11351-11366
Publication Date(Web):28 Mar 2013
DOI:10.1039/C3RA40473K
With tunable cavities, the two-dimensional (2D) hydrogen bonded supramolecular networks are receiving increasing attention in surface supramolecular chemistry during the past decade. Herein, we give a brief account of our efforts on the 2D supramolecular host–guest chemistry based on molecular networks connected by hydrogen bonds, with an aid of scanning tunnelling microscopy (STM) technique. Following the molecular assembling, we have constructed a group of two-dimensional H-bonded supramolecular networks with cavities of different sizes, shapes, and symmetry characteristics on HOPG surface. Our researches have reported that these open porous structures could serve as molecular templates to host alien ensembles, as molecular sieves for molecular separation and recognition, as molecular sensors for ion detections, and as spatial confiners to control chemical reactions. It can be noticed that the interactions between host templates and guest molecules are emphasized throughout this review. On the basis of the confinement of supramolecular networks, it could be less problematic to explore the controllability, predictability, stability and applicability of the ordered structures.
Co-reporter:Jing Xu, Qing-Dao Zeng
Chinese Chemical Letters 2013 Volume 24(Issue 3) pp:177-182
Publication Date(Web):March 2013
DOI:10.1016/j.cclet.2013.02.005
In this review, a group of two-dimensional (2D) hydrogen-bonded supramolecular networks developed in our laboratory are discussed. Our attention is mainly focused on: (1) recognition of Fe3+ through two-component molecular networks; (2) site-selective fabrication of 2D fullerene arrays; and (3) fabrication of the nanoporous structure regulated by photoisomerization reaction process. It is envisioned that special supramolecular nanostructures, through H-bonding interactions, can be constructed or reconstructed to be further investigated toward the research of multi-component systems, molecule recognition, single molecular switches, and host–guest supramolecular chemistry.In this review, a group of two-dimensional (2D) hydrogen-bonded supramolecular networks developed in our laboratory are discussed. Our attention is mainly focused on: (1) recognition of Fe3+ through two-component molecular networks; (2) site-selective fabrication of 2D fullerene arrays; and (3) fabrication of the nanoporous structure regulated by photoisomerization reaction process.
Co-reporter:Xue-mei Zhang, Hai-feng Wang, Shuai Wang, Yong-tao Shen, Yan-lian Yang, Ke Deng, Ke-qing Zhao, Qing-dao Zeng, and Chen Wang
The Journal of Physical Chemistry C 2013 Volume 117(Issue 1) pp:307-312
Publication Date(Web):November 30, 2012
DOI:10.1021/jp3095616
A novel donor–acceptor material based on pyrene derivative with two substituted triphenylenes (Py-TP2) is synthesized via the Sonogashira coupling reaction. The structure and physical chemistry properties of the target molecule have been discussed, ranging from the traditional 1H NMR and high-resolution mass spectroscopy (HRMS), over UV and PL spectra, and to the surface science research. The results revealed that the Py-TP2 molecule shows a narrowed energy gap between LUMO–HOMO and a bathochromic shift of 27 nm in the solid state as compared to that in solution, which is important for its practical applications in optoeletronic devices. Moreover, combined with DFT calculations, our STM results clearly show that the Py-TP2 molecule assembled into a stable long-ranged zigzag structure on HOPG surface. The interesting results in this contribution will boost the physical chemistry study of other functional materials under such methods.
Co-reporter:Dr. Yong-Tao Shen;Dr. Ning-Bo Zhu;Xue-Mei Zhang; Shengbin Lei; Zhongqing Wei;Dr. Min Li; Dahui Zhao; Qing-Dao Zeng; Chen Wang
ChemPhysChem 2013 Volume 14( Issue 1) pp:92-95
Publication Date(Web):
DOI:10.1002/cphc.201200730
Co-reporter:Dr. Xue-Mei Zhang; Qing-Dao Zeng; Chen Wang
Chemistry – An Asian Journal 2013 Volume 8( Issue 10) pp:2330-2340
Publication Date(Web):
DOI:10.1002/asia.201300605
Abstract
Reversible supramolecular self-assemblies have attracted increasing attention in nanoscience and technology during the past few years due to their potential application in the extreme miniaturization of switches and other devices. The building blocks concerned can respond structurally, electronically, optically, and mechanically to external stimuli. Herein, we focus on the recent progress of the supramolecular self-assembly reversibly triggered by temperature, light, electric current, metal ions and protons at the solid–liquid interface. Following this general roadmap, supramolecular systems based on H-bonds, azobenzene derivatives, triple-decker complexes, and the guanine motif are successively discussed in this review. Notably, these reversible phase transformations can be probed by the scanning tunneling microscopy (STM) technique, which has been proven as an effective tool in surface science.
Co-reporter:Xuemei Zhang, Shuai Wang, Yongtao Shen, Yuanyuan Guo, Qingdao Zeng and Chen Wang
Nanoscale 2012 vol. 4(Issue 16) pp:5039-5042
Publication Date(Web):14 Jun 2012
DOI:10.1039/C2NR31186K
Two-dimensional photosensitive supramolecular assemblies based on an azobenzene derivative and bi-pyridine are built up and investigated using scanning tunneling microscopy (STM). In order to probe the photo-induced self-assembled behavior of these two molecules, irradiation experiments with different wavelengths are designed and performed. Our STM results show that the constructed H-bonded networks can be reversibly regulated under irradiation with UV light and visible light.
Co-reporter:Yibao Li, Keqing Zhao, Yanlian Yang, Ke Deng, Qingdao Zeng and Chen Wang
Nanoscale 2012 vol. 4(Issue 1) pp:148-151
Publication Date(Web):08 Nov 2011
DOI:10.1039/C1NR11168J
Two-component supramolecular networks have been constructed with a symmetric triphenylene derivative with three carboxyl groups (sym-TTT) and melamine. Two kinds of hydrogen bonds with different strength are involved in the multi-component self-assembly, one is H-bond between carboxyl group of sym-TTT and melamine, the other is intermolecular H-bond between melamine molecules. These interactions drive a structural transformation from close-packed network to hexagonal network with active amino groups inside of the cavity. Scanning tunneling microscopy (STM) measurements reveal that the functionalized network of sym-TTT/melamine could recognise Fe3+. These results could be helpful for designing functionalized molecular networks by multi-component self-assembling strategy.
Co-reporter:Xue-mei Zhang, Shan-dong Xu, Min Li, Yong-tao Shen, Zhong-qing Wei, Shuai Wang, Qing-dao Zeng, and Chen Wang
The Journal of Physical Chemistry C 2012 Volume 116(Issue 16) pp:8950-8955
Publication Date(Web):April 2, 2012
DOI:10.1021/jp2115884
In this paper, an azobenzene derivative containing two diacetylene groups is synthesized and its self-assembly at a surface investigated using scanning tunneling microscopy (STM). Both the azo-benzene and diacetylene groups are photoactive, and the results show that surface assemblies of the targeted compound undergo polymerization following irradiation at 254 nm and reversible isomerization following alternating irradiation at 365 nm and with visible light. This is the first report of a STM investigation observing both photopolymerization and photoisomerization simultaneously for the same molecular assembly at an interface. The target molecule allows one to induce sequential and reversible structural changes to surface assemblies via multiple optical treatments, and is thus of both fundamental interest for surface science and engineering. These results provide experimental and theoretical guidance for the fabrication of future molecular optoelectronic devices.
Co-reporter:Yong-Tao Shen, Ke Deng, Xue-Mei Zhang, Wei Feng, Qing-Dao Zeng, Chen Wang, and Jian Ru Gong
Nano Letters 2011 Volume 11(Issue 8) pp:3245-3250
Publication Date(Web):July 6, 2011
DOI:10.1021/nl201504x
Controlled regulation of the switchable behavior of the supramolecular network is central to the potential application in the molecular scale nanodevices. In this work, it is reported that the reversible accommodation of the guest molecules in the nanoporous supramolecular network can be regulated by the UV/visible light. The nanoporous complex template of TCDB/4NN-Macrocycle(trans,trans,trans,trans) with photosensitive units is well-defined. After the UV irradiation, the template can be switched on to encapsulate coronene molecules due to the formation of a new photoisomer(trans,cis,trans,cis) and switched off to expel coronene from the inner cavities under the visible light. The photoregulated switchable multicomponent supramolecular guest–host network provides a novel strategy for fabricating the functional nanodevices at the molecular scale.
Co-reporter:Yongtao Shen, Lijin Zeng, Da Lei, Xuemei Zhang, Ke Deng, Yiyu Feng, Wei Feng, Shengbin Lei, Shufei Li, Lihua Gan, Qingdao Zeng and Chen Wang
Journal of Materials Chemistry A 2011 vol. 21(Issue 24) pp:8787-8791
Publication Date(Web):12 May 2011
DOI:10.1039/C1JM10260E
The nanoporous network formed by 1,3,5-tris(10-carboxydecyloxy) benzene (TCDB) was used as the host nanoporous network. It has been identified that a variety of guest molecules (such as triphenylene, 1-phenyloctane and copper(II) phthalocyanine (CuPc)) can be dispersed in this template to form binary supramolecular architectures, which were studied by scanning tunneling microscopy (STM). It is interesting to observe that the host network can adjust itself in response to the molecular size and shape of the guest, and the guest molecules can be excluded by some other guest molecules. The dynamics of CuPc molecules entrapped in TCDB is reported. The STM images as well as the density-functional theory (DFT) calculations reveal that the guest selectivity depends not only on geometry of guest molecules, but also on their adsorption energy in host networks.
Co-reporter:Rui Zhang, Lian-cheng Wang, Min Li, Xue-mei Zhang, Yi-bao Li, Yong-tao Shen, Qi-yu Zheng, Qing-dao Zeng and Chen Wang
Nanoscale 2011 vol. 3(Issue 9) pp:3755-3759
Publication Date(Web):27 Jul 2011
DOI:10.1039/C1NR10387C
Hexaphenylbenzene (HPB) derivatives, HPB-6a and HPB-6pa, can form a supramolecular network which is stabilized by the intermolecular hydrogen bonding between carboxyl group at an octanoic acid/graphite interface. The observation of the heterogeneous bilayer structure formed exclusively by coronene and HPB-6pa at the octanoic acid/graphite interface is reported. Pronounced selectivity of coronene for the supramolecular networks with different sizes is reflected through the formation of bilayer structure for HPB-6pa network with the introduction of coronene as the guest species, indicating stronger interactions between HPB-6pa and coronene.
Co-reporter:Xiaokang Li, Xiaohui He, Yiwang Chen, Xiaolin Fan, Qingdao Zeng
Journal of Molecular Structure 2011 Volume 1002(1–3) pp:145-150
Publication Date(Web):14 September 2011
DOI:10.1016/j.molstruc.2011.07.013
Three new Z-shaped supramolecular complexes (C44H28N4Zn)2·(C14H14N4O2)·(C6H5Cl)4(1), (C44H28N4Zn)2·(C14H14N4O2)·(CH2ClCH2Cl)2·(H2O)4 (2), and (C32H16N8Zn)2·(C14H14N4O2)·(DMF)4 (3) have been prepared by Zinc tetraphenylporphyrin(ZnTPP) and/or Zinc phthalocyanine(ZnPc) with bis(pyridyl) ligands (pyCH2NHCOCONHCH2py, py = 3 or 4-pyridyl), which are ditopic ‘Z’ type ligands. In all of the complexes the central Zn atom is equatorially coordinated by four isoindole N atoms of Pc or TPP macrocycle and axially by N atom of bis(pyridyl) ligands. The interaction of the central Zn atom of ZnTPP and ZnPc with the axial N atom of bis(pyridyl) molecule leads to a deviation of Zn from the basal plane towards the bis(pyridyl) ligands by 0.2 Å in complexes 1–3. The electronic absorption spectra and fluorescence spectra reveal that all of the three supramolecular complexes have a blue-shift and display strong fluorescence.Highlights► Three novel Z-shaped supramolecular complexes have been prepared by ZnTPP and ZnPc with bis(pyridyl) ligands, respectively. ► All of the three supramolecular complexes have a blue-shift and display strong fluorescence. ► The fluorescence spectra should be related to TPP, Pc macrocycle and the axial ligands.
Co-reporter:Dr. Yong-Tao Shen ;Ningbo Zhu;Xue-Mei Zhang;Dr. Ke Deng; Wei Feng;Qifan Yan; Shengbin Lei; Dahui Zhao; Qing-Dao Zeng; Chen Wang
Chemistry - A European Journal 2011 Volume 17( Issue 25) pp:7061-7068
Publication Date(Web):
DOI:10.1002/chem.201003589
Abstract
The unfolding process and self-assembly of a foldable oligomer (foldamer 1) at the liquid/graphite interface were investigated by scanning tunnelling microscopy. At the level of molecular conformation, we identified several molecular conformations (Az, B, C, D, E) that represent intermediate states during unfolding, which may help to elucidate the unfolding process at the liquid/graphite interface. Adsorption at the interface traps the intermediate states of the unfolding process, and STM has proved to be a powerful technique for investigating folding and unfolding of a foldamer at the molecular level, which are not accessible by other methods. The STM observations also revealed that varying the solvent and/or concentration results in different self-assemblies of foldamer 1 as a result of variations in molecular conformations. The solvent and concentration effects were attributed to the changes in existing states (extended or folded) of foldamers in solution, which in turn affect the distribution of adsorbed molecular conformations at the interface. This mechanism is quite different from other systems in which solvent and concentration effects were also observed.
Co-reporter:Yibao Li ; Junhua Wan ; Ke Deng ; Xiaona Han ; Shengbin Lei ; Yanlian Yang ; Qiyu Zheng ; Qingdao Zeng ;Chen Wang
The Journal of Physical Chemistry C 2011 Volume 115(Issue 14) pp:6540-6544
Publication Date(Web):March 23, 2011
DOI:10.1021/jp1097876
We have designed and synthesized one molecular building block, an aromatic trialdehyde derivative with three aldehyde groups, to form a potentially active structure. The scanning tunneling microscopy (STM) images show that the trialdehyde derivative forms lamellar structures. By the addition of active reactant, 5-aminoisophthalic acid, it is found that the structure of the adlayer can be transformed from lamellar to hexagonal structure as was expected. The structural formation of molecular networks is attributed to the condensation reaction between aldehyde and amine. Density functional theory (DFT) calculations reveal the observation of structural transformation at the solid/liquid interface due to the more stable adsorption of the triimine product than that of the trialdehyde derivative.
Co-reporter:Yong-tao Shen ; Ke Deng ; Xue-mei Zhang ; Da Lei ; Ye Xia ; Qing-dao Zeng ;Chen Wang
The Journal of Physical Chemistry C 2011 Volume 115(Issue 40) pp:19696-19701
Publication Date(Web):August 31, 2011
DOI:10.1021/jp202890y
The formation of crystalline multicomponent 2D lattices, containing more than two different organic molecular building blocks, has been rarely achieved because optimized recognition and selection processes require us to achieve the targeted multicomponent surface confined patterns. In this Article, we show that tetraacidic azobenzene (NN4A) and 1,3,5-tris(10-carboxydecyloxy)-benzene (TCDB) molecules can exclusively form 2D phase-separated nanoporous networks via hydrogen bonds between carboxyl groups at the liquid–solid interface, which have two types of cavities with different size and symmetry. These networks can serve as organic templates for the accommodation of fullerene (C60), coronene, and copper(II) phthalocyanine (CuPc) molecules. The experimental and calculated results indicate that coronene can be immobilized in the cavities formed by both NN4A and TCDB, whereas CuPc can be immobilized only in the cavity formed by TCDB and C60 can be immobilized only in the cavity formed by NN4A. Moreover, in the phase-separated networks, the coronene can be preferentially immobilized in NN4A. These results could benefit the studies on highly selectively molecular recognition and separation.
Co-reporter:Yibao Li, Ke Deng, Xingkui Wu, Shengbin Lei, Keqing Zhao, Yanlian Yang, Qingdao Zeng and Chen Wang
Journal of Materials Chemistry A 2010 vol. 20(Issue 41) pp:9100-9103
Publication Date(Web):14 Sep 2010
DOI:10.1039/C0JM01619E
We have designed two molecular building blocks, 2,6,11-tricarboxydecyloxy-3,7,10-triundecyloxy triphenylene (asym-TTT) and 2,6,10-tricarboxydecyloxy-3,7,11-triundecyloxy triphenylene (sym-TTT) with asymmetric and symmetric carboxyl groups, to construct distinct supramolecular networks. The supramolecular network of asym-TTT facilitates the formation of the directional-oriented molecular arrays of zinc phthalocyanines (ZnPc). The high-resolution scanning tunneling microscopic (STM) images as well as the density-functional theory (DFT) calculations reveal the preferential adsorption of ZnPc dimers in the anisotropic rearrangement of an asym-TTT supramolecular network. The self-repairing process of the molecular arrays after sweeping ZnPc dimers further confirms the anisotropic reconstruction of the asym-TTT network. The controlled experiments on the symmetrically substituted compound indicate the impact of the asymmetrically substituted carboxyl groups on the supramolecular networks.
Co-reporter:Min Li, Hai-Jun Xu, Ke Deng, Zhen Shen, Xiao-Zeng You, Qing-Dao Zeng and Chen Wang
The Journal of Physical Chemistry C 2010 Volume 114(Issue 4) pp:1881-1884
Publication Date(Web):January 7, 2010
DOI:10.1021/jp908117c
We present a scanning tunnelling microscopy study on the supramolecular ordering of 21,23-dihydro-5,10,15,20-tetrakis(4-(ethyl 11-phenoxyundecanoate) porphyrin (ester alkyl-TTPP) molecules on a highly oriented pyrolytic graphite surface. Ester alkyl-TTPP formed a molecular superlattice structure—an alternating single/double layer pattern on a graphite surface. Two types of adsorption conformations were observed. On the basis of the theoretical calculation and combined with our previous investigations, it is concluded that the molecular adsorption conformation has an appreciable effect on the interactions of molecule−molecule and molecule−substrate after introducing an ester group into the aliphatic chain. Theoretical investigation indicates that the π−π interactions between the porphyrin cores together with the van der Waals interaction between alkyl chains direct the stacking behavior of ester alkyl-TTPP molecules.
Co-reporter:Yong-Tao Shen ; Li Guan ; Xiao-Yang Zhu ; Qing-Dao Zeng ;Chen Wang
Journal of the American Chemical Society 2009 Volume 131(Issue 17) pp:6174-6180
Publication Date(Web):April 14, 2009
DOI:10.1021/ja808434n
The macrocyclic compounds consisting of photosensitive units as parts of the frame have been extensively studied to mimic photoregulated functions in nature. In this paper, controlled assembly of well-ordered arrays of photosensitive macrocyclic rectangles is demonstrated by using a host−guest molecular template. 4NN-Macrocycle molecules are observed to photoisomerize from trans−trans−trans−trans (t,t,t,t) to a range of isomers including trans−trans−trans−cis (t,t,t,c) and trans−cis−trans−cis (t,c,t,c) isomers after irradiation of UV light. The photoisomers are also observed to affect the guest−host network characteristic appreciably. In the STM observations we can distinguish three (t,t,t,t) conformational isomers, three (t,t,t,c) conformational isomers, and one (t,c,t,c) isomer, which self-assemble into different adlayers with TCDB on a HOPG surface. This study provides a facile approach to study the photoisomerization processes of the azobenzene groups and the conformational photoisomers.
Co-reporter:Min Li Dr.;Ke Deng Dr.;Sheng-Bin Lei Dr.;Yan-Lian Yang Dr.;Tai-Shan Wang Dr.;Yong-Tao Shen Dr.;Chun-Ru Wang Dr.;Chen Wang Dr.
Angewandte Chemie International Edition 2008 Volume 47( Issue 35) pp:6717-6721
Publication Date(Web):
DOI:10.1002/anie.200802518
Co-reporter:Min Li ; Yan-Lian Yang ; Ke-Qing Zhao ; Qing-Dao Zeng ;Chen Wang
The Journal of Physical Chemistry C 2008 Volume 112(Issue 27) pp:10141-10144
Publication Date(Web):June 13, 2008
DOI:10.1021/jp077080e
Binary supramolecular assemblies formed by heterogeneous hydrogen bonds of O···H−O and N···H−O mediated by 4,4′bipyridine (Bpy) were observed using scanning tunneling microscopy (STM) on highly oriented pyrolytic graphite (HOPG) surfaces under ambient conditions. The building units of the assemblies could be attributed to the combinatory molecular motifs of acid−bipyridine−acid formed through the strong N···H−O intermolecular hydrogen bonding.
Co-reporter:Yan-fang Geng, Ping Li, Ji-zhen Li, Xue-mei Zhang, Qing-dao Zeng, Chen Wang
Coordination Chemistry Reviews (15 April 2017) Volume 337() pp:
Publication Date(Web):15 April 2017
DOI:10.1016/j.ccr.2017.01.014
•Supramolecular coordination chemistry has a large impact on a broad of applications.•The coordination structures, dynamics and reactivity are important research themes.•So far, STM technique has opened new doorways to study these concepts on surfaces.•A comprehensive discussion of coordination chemistry studied by STM is significant.Supramolecular coordination chemistry is currently a very popular topic in metallorganic chemistry and has a very large impact on a broad field of applications. More importantly, the invention of STM has opened new doorways to study these concepts on surfaces. This review summarizes the recent progress on surface-confined metallosupramolecular engineering based on the supramolecular coordination chemistry, with the aid of STM. At the beginning, a discussion of metalloids, alkali metals, and alkaline earth metal-based metallosupramolecular engineering is conducted. Next, transition metal-based coordination chemistry on surfaces is discussed. Then, polygonal, double- and triple-decker structures based on rare-earth-metal coordination chemistry are presented. Based on these supramolecular structures, the dynamics of coordination as well as the formed supramolecules are discussed. In the end, the coordination chemistry, including stability of coordination bonds, organic molecules, and gas molecule adsorption is described. Throughout this review, the coordination structures, dynamics and reactivity have been emphasized, which are important current and future research themes.
Co-reporter:Yibao Li, Chunhua Liu, Yunzhi Xie, Xiaokang Li, Xun Li, Xiaolin Fan, Ke Deng, Qingdao Zeng and Chen Wang
Physical Chemistry Chemical Physics 2013 - vol. 15(Issue 1) pp:NaN128-128
Publication Date(Web):2012/10/24
DOI:10.1039/C2CP43244G
We investigate the influence of temperature on the self-assembly of 2,6,11-tricarboxydecyloxy-3,7,10-triundecyloxy triphenylene (asym-TTT) adsorbed on HOPG using scanning tunneling microscopy (STM) at the liquid/solid interface. We show that the packing structures of 2D self-assembled asym-TTT can be precisely tuned by adjusting the substrate temperature. The temperature change from 20 °C to 35 °C induces two phase transitions and increment in the packing density from 0.161 to 0.179 molecules per nm2. The density-functional theory (DFT) calculations reveal that their interaction energies are similar. In particular, the experimental findings further illustrate the preferential adsorption of guest molecules, such as phthalocyanine, only in the domain of more close packing structures.
Co-reporter:Min Li, Peng Xie, Ke Deng, Yan-Lian Yang, Sheng-Bin Lei, Zhong-Qing Wei, Qing-Dao Zeng and Chen Wang
Physical Chemistry Chemical Physics 2014 - vol. 16(Issue 19) pp:NaN8782-8782
Publication Date(Web):2014/03/18
DOI:10.1039/C3CP55355H
In the present work flexible binary networks of 1,3,5-benzenetricarboxylic acid (TMA) with 4,4′-bipyridine (Bpy) or 1,3,5-tris(4-pyridyl)-2,4,6-triazine(TPTZ) molecules at the liquid–solid interface were constructed. When coronene (COR) molecules are introduced into these systems, the binary networks collapse and at the same time, new COR/TMA host–guest structures are formed. Both experiments and calculations unambiguously indicate that the COR/TMA host–guest complex structure has stronger adsorption energy, resulting in the deconstruction–reconstruction phenomenon.
Co-reporter:Siqi Zhang, Junyong Zhang, Ke Deng, Jingli Xie, Wubiao Duan and Qingdao Zeng
Physical Chemistry Chemical Physics 2015 - vol. 17(Issue 37) pp:NaN24467-24467
Publication Date(Web):2015/08/24
DOI:10.1039/C5CP04065E
In the present investigation, we reported the fabrication of a chicken-wire porous 2D network formed by triphenylene-2,6,10-tricarboxylic acid (H3TTCA) at the liquid–solid interface. When coronene (COR) molecules were added into the system, the H3TTCA honey-comb network was broken and the reconstructed structures of the H3TTCA/COR host–guest systems were subsequently formed. Scanning tunneling microscopic (STM) measurements and density function theory (DFT) calculations were utilized to reveal the structural variety in the co-assembly of H3TTCA/COR controlled by the solution concentration at 1-heptanoic acid/HOPG interface.
Co-reporter:Shuai Wang, Fengying Zhao, Shiwen Luo, Yanfang Geng, Qingdao Zeng and Chen Wang
Physical Chemistry Chemical Physics 2015 - vol. 17(Issue 18) pp:NaN12355-12355
Publication Date(Web):2015/04/09
DOI:10.1039/C5CP00531K
Variable supramolecular structures constructed by bis-(2,2′:6′,2′′-terpyridine)-4′-oxyhexadecane (BT-O-C16) on a highly oriented pyrolytic graphite (HOPG) surface were investigated by scanning tunneling microscopy (STM). Seven different solvents (1-phenyloctane, n-tetradecane, n-dodecane, n-decane, n-octane, 1-heptanoic acid, and 1-octanoic acid) were utilized to affect the self-assembling structures of BT-O-C16 at liquid/HOPG interfaces. High-resolution STM analyses revealed that various nanostructures were formed by the change of molecular conformation, which are actually driven by the cooperative interaction effect under different environments. Therefore, the solvent-induced cooperative influence on the molecular self-assembly is important for constructing supramolecular nanostructures.
Co-reporter:Yibao Li, Ke Deng, Xingkui Wu, Shengbin Lei, Keqing Zhao, Yanlian Yang, Qingdao Zeng and Chen Wang
Journal of Materials Chemistry A 2010 - vol. 20(Issue 41) pp:NaN9103-9103
Publication Date(Web):2010/09/14
DOI:10.1039/C0JM01619E
We have designed two molecular building blocks, 2,6,11-tricarboxydecyloxy-3,7,10-triundecyloxy triphenylene (asym-TTT) and 2,6,10-tricarboxydecyloxy-3,7,11-triundecyloxy triphenylene (sym-TTT) with asymmetric and symmetric carboxyl groups, to construct distinct supramolecular networks. The supramolecular network of asym-TTT facilitates the formation of the directional-oriented molecular arrays of zinc phthalocyanines (ZnPc). The high-resolution scanning tunneling microscopic (STM) images as well as the density-functional theory (DFT) calculations reveal the preferential adsorption of ZnPc dimers in the anisotropic rearrangement of an asym-TTT supramolecular network. The self-repairing process of the molecular arrays after sweeping ZnPc dimers further confirms the anisotropic reconstruction of the asym-TTT network. The controlled experiments on the symmetrically substituted compound indicate the impact of the asymmetrically substituted carboxyl groups on the supramolecular networks.
Co-reporter:Xianghua Zeng, Xiaojing Yao, Junyong Zhang, Qi Zhang, Wenqian Wu, Aihua Chai, Jinlan Wang, Qingdao Zeng and Jingli Xie
Inorganic Chemistry Frontiers 2015 - vol. 2(Issue 2) pp:NaN169-169
Publication Date(Web):2014/12/19
DOI:10.1039/C4QI00227J
A series of chalcogenide compounds with various compositions, i.e., octanuclear or tetranuclear Zn–S clusters, have been synthesised in a straighforward manner. Different fused-ring aromatic ligands were used as capping ligands and the corresponding zero-dimensional (0D) products were obtained. On the other hand, use of bridging ligands led to a family of one-dimensional (1D) coordination polymers, and an in situ ligand reaction has been observed in [Zn8S(SC6H5)13L1(H2O)]·2H2O (L = 3-carboxypryidyl) due to the hydrolysis of the cyano group of 3-pyridinecarbonitrile. A very rare 1D helical-chain structure was observed in [Zn4(SC6H5)8L1] (L = 4,4′-bipyridyl), providing evidence of the character of bridging organic ligands in the corresponding crystalline materials. First-principles calculations on [Zn4(SC6H5)8L1] (L = 4,4′-bipyridyl) further revealed that the two cluster units could rotate freely about the C–C single bond over a broad range, eventually leading to the formation of a one-dimensional helical structure.
Co-reporter:Yongtao Shen, Lijin Zeng, Da Lei, Xuemei Zhang, Ke Deng, Yiyu Feng, Wei Feng, Shengbin Lei, Shufei Li, Lihua Gan, Qingdao Zeng and Chen Wang
Journal of Materials Chemistry A 2011 - vol. 21(Issue 24) pp:NaN8791-8791
Publication Date(Web):2011/05/12
DOI:10.1039/C1JM10260E
The nanoporous network formed by 1,3,5-tris(10-carboxydecyloxy) benzene (TCDB) was used as the host nanoporous network. It has been identified that a variety of guest molecules (such as triphenylene, 1-phenyloctane and copper(II) phthalocyanine (CuPc)) can be dispersed in this template to form binary supramolecular architectures, which were studied by scanning tunneling microscopy (STM). It is interesting to observe that the host network can adjust itself in response to the molecular size and shape of the guest, and the guest molecules can be excluded by some other guest molecules. The dynamics of CuPc molecules entrapped in TCDB is reported. The STM images as well as the density-functional theory (DFT) calculations reveal that the guest selectivity depends not only on geometry of guest molecules, but also on their adsorption energy in host networks.
Co-reporter:Xuemei Zhang, Haijun Xu, Yongtao Shen, Yibing Wang, Zhen Shen, Qingdao Zeng and Chen Wang
Physical Chemistry Chemical Physics 2013 - vol. 15(Issue 30) pp:NaN12515-12515
Publication Date(Web):2013/05/14
DOI:10.1039/C3CP51586A
In this paper, a novel core-modified porphyrin with meso-aryl substituents and phenanthrene-fused pyrrole rings (N2S2–OR) is synthesized. Scanning tunneling microscopy (STM) has been used to probe its self-assembly behavior on a highly-oriented pyrolytic graphite (HOPG) surface. Our STM results have shown that there is an obvious solvent-dependent self-assembly for the surface-confined target molecules. In n-tetradecane, N2S2–OR assembles into a perfect alternating structure. At the 1-phenyloctane–graphite interface, disordered structures are formed and nonperiodic alternation is observed, whereas the target molecule in 1-heptanoic acid is assumed to form homogeneous close-packed monolayers with no alternating. Interestingly, such solvent-dependent supramolecular assembled behavior also involves the structural transformation of the backbone of the core-modified porphyrin derivative from saddle to reversed-saddle in these three solvents with different polarities.
Co-reporter:Yong-Tao Shen, Li Guan, Xue-Mei Zhang, Shuai Wang, Li-Hua Gan, Qing-Dao Zeng and Chen Wang
Physical Chemistry Chemical Physics 2013 - vol. 15(Issue 30) pp:NaN12479-12479
Publication Date(Web):2013/03/28
DOI:10.1039/C3CP50371B
2D porous networks have attracted great attention as they can be used to immobilize functional units as guest molecules in a spatially ordered arrangement. In this work, a novel molecular hybrid network with two kinds of cavities was fabricated. Several kinds of guest molecules, such as coronene, copper(II) phthalocyanine (CuPc), triphenylene, heptanoic acid and fullerene molecules, can be immobilized into this template. Site- and size-selective effects can be observed. Furthermore, we have also fabricated interesting 2D crystal architecture with complex four-component structure at the liquid–solid interface, following investigation by scanning tunnelling microscopy (STM). The current findings provide a convenient approach towards the formation of more complex and functionalized surface nanopatterns, which can benefit the study of host–guest assembly behaviour within a monolayer composed by several components at interfaces.
Co-reporter:JinDong Xue, Jing Xu, FangYun Hu, LingYan Liao, Min Li, WuBiao Duan, QingDao Zeng and Chen Wang
Physical Chemistry Chemical Physics 2014 - vol. 16(Issue 47) pp:NaN25769-25769
Publication Date(Web):2014/10/21
DOI:10.1039/C4CP04154B
Efficient photochemical reactions on a surface are of great importance for their potential applications in optoelectronic devices. In this work, a highly efficient photodimerization reaction of an olefin cocrystal built from two trans-1,2-bis(4-pyridyl)ethylenes (4,4′-bpe) and two isophthalic acid molecules via N⋯H–O hydrogen bonds in between was achieved in a nanotemplate on a highly oriented pyrolytic graphite (HOPG) surface. 4,4′-Bpe molecules first undergo the trans–cis isomerization followed by [2+2] photodimerization in the nanotemplate on HOPG upon UV irradiation. The efficiency of the isomerization as well as the photodimerization in the presence of the nanotemplate is much higher than that in its absence. These results provide a facile way to achieve highly efficient photodimerization of olefins on a large scale on surfaces.
Co-reporter:Yibao Li, Chunhua Liu, Yunzhi Xie, Xun Li, Xiaolin Fan, Lihua Yuan and Qingdao Zeng
Chemical Communications 2013 - vol. 49(Issue 79) pp:NaN9023-9023
Publication Date(Web):2013/08/09
DOI:10.1039/C3CC44978E
The K+-induced switching of valinomycin has been studied using a molecular template formed by an aromatic oligoamide macrocycle at the liquid/solid interface by scanning tunneling microscopy (STM). Individual valinomycin and its K+ complex can be identified and resolved in the molecular template, and the high-resolution STM images of valinomycin and its K+ complex show triangle-like and cyclic structural characteristics, respectively.
Co-reporter:Yanfang Geng, Miaoqing Liu, Jindong Xue, Peng Xu, Yifei Wang, Lijin Shu, Qingdao Zeng and Chen Wang
Chemical Communications 2015 - vol. 51(Issue 31) pp:NaN6823-6823
Publication Date(Web):2015/03/12
DOI:10.1039/C5CC01032B
An amine-substituted macrocycle 6Y, a rigid hexagonal ring, self-assembled into network architecture on the surface, which could be used as a molecular template to directly fabricate gold nanoparticles (AuNPs) with narrow size distribution (2.2 ± 0.1 nm). This work demonstrated a new pathway for the formation of controllable AuNPs on the surface.
Co-reporter:Dapeng Luo, Xuemei Zhang, Yongtao Shen, Jing Xu, Lijin Shu, Qingdao Zeng and Chen Wang
Chemical Communications 2014 - vol. 50(Issue 66) pp:NaN9371-9371
Publication Date(Web):2014/06/20
DOI:10.1039/C4CC02120G
A tetraethylene glycol ether bridged derivative 9 has been designed and synthesized, and its two-dimensional (2D) self-assembled behavior has been investigated at the single-molecule level. Our results revealed that 9 generally adopted the fully extended state but changed to the contracted state when triggered by K2CO3, and recovered the original fully extended conformation after subsequent addition of 18-crown-6. Such a coordination-controlled reversible assembly reveals supramolecular springs in response to chemical stimuli, which is of great interest in bionics and materials science.
![Zinc, [5,10,15,20-tetraphenyl-21H,23H-porphinato(2-)-κN21,κN22,κN23,κN24]-, (SP-4-1)-](/data/chemimg/478800/14074-80-7.png)
![Zinc, [5,10,15,20-tetraphenyl-21H,23H-porphinato(2-)-κN21,κN22,κN23,κN24]-, (SP-4-1)-](/data/chemimg/478800/14074-80-7_b.png)
![Undecanoic acid, 11,11',11''-[1,3,5-benzenetriyltris(oxy)]tris-](http://img.cochemist.com/ccimg/92700/92631-02-2.png)
![Undecanoic acid, 11,11',11''-[1,3,5-benzenetriyltris(oxy)]tris-](http://img.cochemist.com/ccimg/92700/92631-02-2_b.png)