Co-reporter:Xinxin Jiang, Shaohua Zhang, Feng Ren, Lei Chen, Jianfeng Zeng, Mo Zhu, Zhenxiang Cheng, Mingyuan Gao, and Zhen Li
ACS Nano June 27, 2017 Volume 11(Issue 6) pp:5633-5633
Publication Date(Web):May 19, 2017
DOI:10.1021/acsnano.7b01032
Nanoscale ternary chalcogenides have attracted intense research interest due to their wealth of tunable properties and diverse applications in energy and environmental and biomedical fields. In this article, ultrasmall magnetic CuFeSe2 ternary nanocrystals (<5.0 nm) were fabricated in the presence of thiol-functionalized poly(methacrylic acid) by an environmentally friendly aqueous method under ambient conditions. The small band gap and the existence of intermediate bands lead to a broad NIR absorbance in the range of 500–1100 nm and high photothermal conversion efficiency (82%) of CuFeSe2 nanocrystals. The resultant CuFeSe2 nanocrystals show superparamagnetism and effective attenuation for X-rays. In addition, they also exhibit excellent water solubility, colloidal stability, biocompatibility, and multifunctional groups. These properties enable them to be an ideal nanotheranostic agent for multimodal imaging [e.g., photoacoustic imaging (PAI), magnetic resonance imaging (MRI), computed tomography (CT) imaging] guided photothermal therapy of cancer.Keywords: magnetic CuFeSe2; multimodal imaging; photothermal therapy; ternary semiconductors; ultrasmall nanocrystals;
Co-reporter:Qiao Sun;Gangqiang Qin;Yingying Ma;Weihua Wang;Ping Li;Aijun Du
Nanoscale (2009-Present) 2017 vol. 9(Issue 1) pp:19-24
Publication Date(Web):2016/12/22
DOI:10.1039/C6NR07001A
Developing new materials and technologies for efficient CO2 capture, particularly for separation of CO2 post-combustion, will significantly reduce the CO2 concentration and its impacts on the environment. A challenge for CO2 capture is to obtain high performance adsorbents with both high selectivity and easy regeneration. Here, CO2 capture/regeneration on MoS2 monolayers controlled by turning on/off external electric fields is comprehensively investigated through a density functional theory calculation. The calculated results indicate that CO2 forms a weak interaction with MoS2 monolayers in the absence of an electric field, but strongly interacts with MoS2 monolayers when an electric field of 0.004 a.u. is applied. Moreover, the adsorbed CO2 can be released from the surface of MoS2 without any energy barrier once the electric field is turned off. Compared with the adsorption of CO2, the interactions between N2 and MoS2 are not affected significantly by the external electric fields, which indicates that MoS2 monolayers can be used as a robust absorbent for controllable capture of CO2 by applying an electric field, especially to separate CO2 from the post-combustion gas mixture where CO2 and N2 are the main components.
Co-reporter:Hang T. Ta, Zhen Li, Christoph E. Hagemeyer, Gary Cowin, Shaohua Zhang, Jathushan Palasubramaniam, Karen Alt, Xiaowei Wang, Karlheinz Peter, Andrew K. Whittaker
Biomaterials 2017 Volume 134(Volume 134) pp:
Publication Date(Web):1 July 2017
DOI:10.1016/j.biomaterials.2017.04.037
Magnetic resonance imaging (MRI) is a powerful and indispensable tool in medical research, clinical diagnosis, and patient care due to its high spatial resolution and non-limited penetration depth. The simultaneous use of positive and negative MRI imaging that employs the same contrast agents will significantly improve detection accuracy. Here we report the development of functional multimodal iron oxide nanoparticles for targeted MRI of atherothrombosis using a combination of chemical and biological conjugation techniques. Monodisperse, water-soluble and biocompatible ultra-small magnetic dual contrast iron oxide nanoparticles (DCIONs) were generated using a high-temperature co-precipitation route and appeared to be efficient positive and negative dual contrast agents for magnetic resonance imaging. Using a unique chemo-enzymatic approach involving copper-free click chemistry and Staphylococcus aureus sortase A enzyme conjugation, DCIONs were functionalized with single-chain antibodies (scFv) directed against activated platelets for targeting purposes. The DCIONs were also labelled with fluorescent molecules to allow for optical imaging. The antigen binding activity of the scFv was retained and resulted in the successful targeting of contrast agents to thrombosis as demonstrated in a range of in vitro and in vivo experiments. T1- and T2-weighted MRI of thrombi was recorded and demonstrated the great potential of dual T1/T2 contrast iron oxide particles in imaging of cardiovascular disease.Download high-res image (183KB)Download full-size image
Co-reporter:Ling Wen;Ling Chen;Shimin Zheng;Jianfeng Zeng;Guangxin Duan;Yong Wang;Guanglin Wang;Zhifang Chai;Mingyuan Gao
Advanced Materials 2016 Volume 28( Issue 25) pp:5072-5079
Publication Date(Web):
DOI:10.1002/adma.201506428
Co-reporter:Chao Han;Qiao Sun;Shi Xue Dou
Advanced Energy Materials 2016 Volume 6( Issue 15) pp:
Publication Date(Web):
DOI:10.1002/aenm.201600498
Due to the urgency of our energy and environmental issues, a variety of cost-effective and pollution-free technologies have attracted considerable attention, among which thermoelectric technology has made enormous progress. Substantial numbers of new thermoelectric materials are created with high figure of merit (ZT) by using advanced nanoscience and nanotechnology. This is especially true in the case of metal-chalcogenide-based materials, which possess both relatively high ZT and low cost among all the different kinds of thermoelectric materials. Here, comprehensive coverage of recent advances in metal chalcogenides and their correlated thermoelectric enhancement mechanisms are provided. Several new strategies are summarized with the hope that they can inspire further enhancement of performance, both in metal chalcogenides and in other materials.
Co-reporter:Yong Wang;Yongyou Wu;Yujing Liu;Jia Shen;Ling Lv;Liubing Li;Liecheng Yang;Jianfeng Zeng;Yangyun Wang;Leshuai W. Zhang;Mingyuan Gao;Zhifang Chai
Advanced Functional Materials 2016 Volume 26( Issue 29) pp:5335-5344
Publication Date(Web):
DOI:10.1002/adfm.201601341
Fabrication of ultrasmall single-component omnipotent nanotheranostic agents integrated with multimodal imaging and multiple therapeutic functions becomes more and more practically relevant but challenging. In this article, sub 10 nm Bi2S3 biocompatible particles are prepared through a bovine serum albumin (BSA)-mediated biomineralization process under ambient aqueous conditions. Owing to the ultrasmall size and colloidal stability, the resulting nanoparticles (NPs) present outstanding blood circulation behavior and excellent tumor targeting ability. Toward theranostic applications, the biosafety profile is carefully investigated. In addition, photothermal conversion is characterized for both photoacoustic imaging and photothermal treatment of cancers. Upon radiolabeling, the performance of the resulting particles for SPECT/CT imaging in vivo is also carried out. Additionally, different combinations of treatments are applied for evaluating the performance of the as-prepared Bi2S3 NPs in photothermal- and radiotherapy of tumors. Due to the remarkable photothermal conversion efficiency and large X-ray attenuation coefficient, the implanted tumors are completely eradicated through combined therapies, which highlights the potential of BSA-capped Bi2S3 NPs as a novel multifunctional nanotheranostic agent.
Co-reporter:Qiao Sun, Caixia Sun, Aijun Du, Shixue Dou and Zhen Li
Nanoscale 2016 vol. 8(Issue 29) pp:14084-14091
Publication Date(Web):28 Jun 2016
DOI:10.1039/C6NR03288E
Exploiting metal-free catalysts for the oxygen reduction reaction (ORR) and understanding their catalytic mechanisms are vital for the development of fuel cells (FCs). Our study has demonstrated that in-plane heterostructures of graphene and boron nitride (G/BN) can serve as an efficient metal-free catalyst for the ORR, in which the C–N interfaces of G/BN heterostructures act as reactive sites. The formation of water at the heterointerface is both energetically and kinetically favorable via a four-electron pathway. Moreover, the water formed can be easily released from the heterointerface, and the catalytically active sites can be regenerated for the next cycle. Since G/BN heterostructures with controlled domain sizes have been successfully synthesized in recent reports (e.g. Nat. Nanotechnol., 2013, 8, 119), our results highlight the great potential of such heterostructures as a promising metal-free catalyst for the ORR in FCs.
Co-reporter:Lijuan Zhang, Jianli Wang, Zhenxiang Cheng, Qiao Sun, Zhen Li and Shixue Dou
Journal of Materials Chemistry A 2016 vol. 4(Issue 20) pp:7936-7942
Publication Date(Web):20 Apr 2016
DOI:10.1039/C6TA01994C
SnTe, with the same rock-salt structure as PbTe, is a potentially attractive thermoelectric material. Pristine SnTe has poor thermoelectric performance because of its very high hole concentration resulting from intrinsic Sn vacancies, which leads to a high thermal conductivity and a low Seebeck coefficient. In this work, the thermoelectric properties of SnTe were modified by doping with different contents of gadolinium and silver. It is found that SnTe doped with optimal gadolinium (i.e. Gd0.06Sn0.94Te) exhibited extraordinarily low lattice thermal conductivity that is close to the theoretical minimum. The drastic reduction of lattice thermal conductivity is attributed to the formation of nanoprecipitates, which strongly scatter phonons by mass fluctuation between a second phase and matrix coupled with mesoscale scattering via grain boundaries. Further doping Gd0.06Sn0.94Te with Ag leads to a higher Seebeck coefficient due to the decreased carrier concentration and adjusted phase composition. Optimal Ag doping leads to a 3 times and 2 times enhancement of the figure of merit (ZT) in comparison with SnTe and Gd0.06Sn0.94Te, respectively, i.e. a ZT of ∼1.1 was obtained for 11 atom% Ag-containing Gd0.06Sn0.94Te at 873 K.
Co-reporter:Chao Han;Yang Bai;Qiao Sun;Shaohua Zhang;Lianzhou Wang;Shixue Dou
Advanced Science 2016 Volume 3( Issue 5) pp:
Publication Date(Web):
DOI:10.1002/advs.201500350
A new aqueous and scalable strategy to synthesize surfactant-free Cu2Te nanotubes and nanosheets at room temperature has been developed. In aqueous solution, Cu2E (E = O, S, Se) nanoparticles can be easily transformed into Cu2Te nanosheets and nanotubes via a simple anion exchange reaction under ambient conditions. The formation of Cu2Te nanosheets is ascribed to a novel exchange-peeling growth mechanism instead of simple Kirkendall effect; and the resultant nanosheets can be further rolled into nanotubes with assistance of stirring. The morphologies of Cu2Te nanosheets and nanotubes can be easily controlled by changing the synthesis parameters, such as the concentration of precursors, the size of nanoparticle precursor, and the amount of NaBH4, as well as the stirring speed. Thus-formed Cu2Te nanostructures exhibit excellent catalytic activity toward sulfide redox shuttles and are exploited as counter electrodes catalysts for quantum dot sensitized solar cells. The performance of Cu2Te nanostructures strongly depends on their morphology, and the solar cells made with counter electrodes from Cu2Te nanosheets show the maximum power conversion efficiency of 5.35%.
Co-reporter:Jianfeng Zeng;Ming Cheng;Yong Wang;Ling Wen;Ling Chen;Yongyou Wu;Mingyuan Gao;Zhifang Chai
Advanced Healthcare Materials 2016 Volume 5( Issue 7) pp:772-780
Publication Date(Web):
DOI:10.1002/adhm.201500898
Co-reporter:Fangxin Mao, Jing Guo, Shaohua Zhang, Fan Yang, Qiao Sun, Jianmin Ma and Zhen Li
RSC Advances 2016 vol. 6(Issue 44) pp:38228-38232
Publication Date(Web):31 Mar 2016
DOI:10.1039/C6RA01301E
Hierarchical S-doped Bi2Se3 microspheres assembled by stacked nanosheets were successfully synthesized as the anode of a lithium ion battery, which shows an initial discharge capacity of 771.3 mA h g−1 with great potential in energy storage.
Co-reporter:Fangxin Mao, Ling Wen, Caixia Sun, Shaohua Zhang, Guanglin Wang, Jianfeng Zeng, Yong Wang, Jianmin Ma, Mingyuan Gao, and Zhen Li
ACS Nano 2016 Volume 10(Issue 12) pp:
Publication Date(Web):November 16, 2016
DOI:10.1021/acsnano.6b06067
Sub-3 nm ultrasmall Bi2Se3 nanodots stabilized with bovine serum albumin were successfully synthesized through a reaction of hydroxyethylthioselenide with bismuth chloride in aqueous solution under ambient conditions. These nanodots exhibit a high photothermal conversion efficiency (η = 50.7%) due to their strong broad absorbance in the near-infrared (NIR) window and serve as a nanotheranostic agent for photoacoustic imaging and photothermal cancer therapy. In addition, they also display radioenhancement with a ratio of 6% due to their sensitivity to X-rays, which makes them a potential sensitizer for radiotherapy. These nanodots were also labled with radioactive 99mTc for quantification of their biodistribution by single-photon-emission computed tomography (SPECT)/computed tomography (CT) imaging. Our work demonstrates the potential of ultrasmall Bi2Se3 nanodots in multimodal imaging-guided synergetic radiophotothermal therapy of cancer.Keywords: bismuth selenide nanodots; bovine serum albumin; multimodal imaging; radiophotothermal therapy; ultrasmall;
Co-reporter:Xin Qi Chen, Zhen Li, and Shi Xue Dou
ACS Applied Materials & Interfaces 2015 Volume 7(Issue 24) pp:13295
Publication Date(Web):May 28, 2015
DOI:10.1021/acsami.5b01085
Grams of copper selenides (Cu2–xSe) were prepared from commercial copper and selenium powders in the presence of thiol ligands by a one-pot reaction at room temperature. The resultant copper selenides are a mixture of nanoparticles and their assembled nanosheets, and the thickness of nanosheets assembled is strongly dependent on the ratio of thiol ligand to selenium powder. The resultant Cu2–xSe nanostructures were treated with hydrazine solution to remove the surface ligands and then explored as a potential thermoelectric candidate in comparison with commercial copper selenide powders. The research provides a novel ambient approach for preparation of Cu2–xSe nanocrystallines on a large scale for various applications.Keywords: copper selenide; semiconductor; thermoelectric properties;
Co-reporter:Chao Han, Zhen Li, Gao Qing (Max) Lu, Shi Xue Dou
Nano Energy 2015 Volume 15() pp:193-204
Publication Date(Web):July 2015
DOI:10.1016/j.nanoen.2015.04.024
•Ambient scalable synthesis of surfactant-free thermoelectric metal chalcogenide nanostructures.•Low cost and environmental friendly aqueous approach.•Extremely low solubility and in-situ release of hydrogen lead to small nanostructures.•Enhanced and comparable thermoelectric properties with bulk and nanoscale analogs fabricated from complex methods.A robust low-cost ambient aqueous method for the scalable synthesis of surfactant-free nanostructured metal chalcogenides (MaXb, M=Cu, Ag, Sn, Pb, and Bi; X=S, Se, and Te; a=1 or 2; and b=1 or 3) is developed in this work. The effects of reaction parameters, such as precursor concentration, ratio of precursors, and amount of reducing agent, on the composition, size, and shape of the resultant nanostructures have been comprehensively investigated. This environmentally friendly approach is capable of producing metal chalcogenide nanostructures in a one-pot reaction on a large scale, which were investigated for their thermoelectric properties towards conversion of waste heat into electricity. The results demonstrate that the thermoelectric properties of these metal chalcogenide nanostructures are strongly dependent on the types of metal chalcogenides, and their figure of merits are comparable with previously reported figures for their bulk or nanostructured counterparts.
Co-reporter:Jinyan Xiong;Chao Han;Shixue Dou
Science Bulletin 2015 Volume 60( Issue 24) pp:2083-2090
Publication Date(Web):2015 December
DOI:10.1007/s11434-015-0972-z
The increasing energy consumption and environmental concerns have driven the development of cost-effective, high-efficiency clean energy. Advanced functional nanomaterials and relevant nanotechnologies are playing a crucial role and showing promise in resolving some energy issues. In this view, we focus on recent advances of functional nanomaterials in clean energy applications, including solar energy conversion, water splitting, photodegradation, electrochemical energy conversion and storage, and thermoelectric conversion, which have attracted considerable interests in the regime of clean energy.
Co-reporter:Yang Bai, Chao Han, Xinqi Chen, Hua Yu, Xu Zong, Zhen Li, Lianzhou Wang
Nano Energy 2015 Volume 13() pp:609-619
Publication Date(Web):April 2015
DOI:10.1016/j.nanoen.2015.04.002
•Novel nanostructured Cu2−xSe photocathodes featuring excellent electrical conductivity and superior electrocatalytic activity were developed.•Pillared nanoporous titania as photoanode led to further light harvesting and charge transfer improvement concurrently.•Simultaneous engineering of photocathode and photoanode boosted the efficiency of quantum dot sensitized solar cell up to 7.11%.We demonstrate a new strategy of boosting the efficiency of quantum dot sensitized solar cells (QDSSCs) by engineering the photocathode and photoanode simultaneously. Nanostructured photocathodes based on non-stoichiometric Cu2−xSe electrocatalysts were developed via a simple and scalable approach for CdS/CdSe QDs co-sensitized solar cells. Compared to Cu2S CE, remarkably improved photovoltaic performance was achieved for QDSSCs with Cu2−xSe CEs. The superior catalytic activity and electrical conductivity of Cu2−xSe CEs were verified by the electrochemical impedance spectra and Tafel-polarization measurements. To maximize the efficiency enhancement, the photoanodes were optimized by introducing a pillared porous titania composite as the scattering layers for further light harvesting and charge transfer improvement concurrently. The combination of effective Cu2−xSe electrocatalysts and pillared titania scattering layers contributed to one of the best reported efficiencies of 7.11% for CdS/CdSe QDs co-sensitized solar cells.
Co-reporter:Qiao Sun ; Caixia Sun ; Aijun Du
The Journal of Physical Chemistry C 2014 Volume 118(Issue 51) pp:30006-30012
Publication Date(Web):November 25, 2014
DOI:10.1021/jp510387h
Natural gas (the main component is methane) has been widely used as a fuel and raw material in industry. Removal of nitrogen (N2) from methane (CH4) can reduce the cost of natural gas transport and improve its efficiency. However, their extremely similar size increases the difficulty of separating N2 from CH4. In this study, we have performed a comprehensive investigation of N2 and CH4 adsorption on different charge states of boron nitride (BN) nanocage fullerene, B36N36, by using a density functional theory approach. The calculational results indicate that B36N36 in the negatively charged state has high selectivity in separating N2 from CH4. Moreover, once the extra electron is removed from the BN nanocage, the N2 will be released from the material. This study demonstrates that the B36N36 fullerene can be used as a highly selective and reusable material for the separation of N2 from CH4. The study also provides a clue to experimental design and application of BN nanomaterials for natural gas purification.
Co-reporter:Caixia Sun, Ling Wen, Jianfeng Zeng, Yong Wang, Qiao Sun, Lijuan Deng, Chongjun Zhao, Zhen Li
Biomaterials (June 2016) Volume 91() pp:81-89
Publication Date(Web):June 2016
DOI:10.1016/j.biomaterials.2016.03.022
Co-reporter:Caixia Sun, Ling Wen, Jianfeng Zeng, Yong Wang, Qiao Sun, Lijuan Deng, Chongjun Zhao, Zhen Li
Biomaterials (June 2016) Volume 91() pp:81-89
Publication Date(Web):June 2016
DOI:10.1016/j.biomaterials.2016.03.022
Black phosphorus (BP) nanostructures such as nanosheets and nanoparticles have attracted considerable attention in recent years due to their unique properties and great potential in various physical, chemical, and biological fields. In this article, water-soluble and biocompatible PEGylated BP nanoparticles with a high yield were prepared by one-pot solventless high energy mechanical milling technique. The resultant BP nanoparticles can efficiently convert near infrared (NIR) light into heat, and exhibit excellent photostability, which makes them suitable as a novel nanotheranostic agent for photoacoustic (PA) imaging and photothermal therapy of cancer. The in-vitro results demonstrate the excellent biocompatibility of PEGylated BP nanoparticles, which can be used for photothermal ablation of cancer cells under irradiation with NIR light. The in-vivo PA images demonstrate that these BP nanoparticles can be efficiently accumulated in tumors through the enhanced permeability retention effect. The resultant BP nanoparticles can be further utilized for photothermal ablation of tumors by irradiation with NIR light. The tumor-bearing mice were completely recovered after photothermal treatment with BP nanoparticles, in comparison with mice from control groups. Our research highlights the great potential of PEGylated BP nanoparticles in detection and treatment of cancer.
Co-reporter:Lijuan Zhang, Jianli Wang, Zhenxiang Cheng, Qiao Sun, Zhen Li and Shixue Dou
Journal of Materials Chemistry A 2016 - vol. 4(Issue 20) pp:NaN7942-7942
Publication Date(Web):2016/04/20
DOI:10.1039/C6TA01994C
SnTe, with the same rock-salt structure as PbTe, is a potentially attractive thermoelectric material. Pristine SnTe has poor thermoelectric performance because of its very high hole concentration resulting from intrinsic Sn vacancies, which leads to a high thermal conductivity and a low Seebeck coefficient. In this work, the thermoelectric properties of SnTe were modified by doping with different contents of gadolinium and silver. It is found that SnTe doped with optimal gadolinium (i.e. Gd0.06Sn0.94Te) exhibited extraordinarily low lattice thermal conductivity that is close to the theoretical minimum. The drastic reduction of lattice thermal conductivity is attributed to the formation of nanoprecipitates, which strongly scatter phonons by mass fluctuation between a second phase and matrix coupled with mesoscale scattering via grain boundaries. Further doping Gd0.06Sn0.94Te with Ag leads to a higher Seebeck coefficient due to the decreased carrier concentration and adjusted phase composition. Optimal Ag doping leads to a 3 times and 2 times enhancement of the figure of merit (ZT) in comparison with SnTe and Gd0.06Sn0.94Te, respectively, i.e. a ZT of ∼1.1 was obtained for 11 atom% Ag-containing Gd0.06Sn0.94Te at 873 K.
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