Co-reporter:Yang Yang; Guangdong Chen; Luz J. Martinez-Miranda; Hua Yu; Kun Liu;Zhihong Nie
Journal of the American Chemical Society 2015 Volume 138(Issue 1) pp:68-71
Publication Date(Web):December 23, 2015
DOI:10.1021/jacs.5b11546
The design and assembly of novel colloidal particles are of both academic and technological interest. We developed a wet-chemical route to synthesize monodisperse bent rigid silica rods by controlled perturbation of emulsion-templated growth. The bending angle of the rods can be tuned in a range of 0–50° by varying the strength of perturbation in the reaction temperature or pH in the course of rod growth. The length of each arm of the bent rods can be individually controlled by adjusting the reaction time. For the first time we demonstrated that the bent silica rods resemble banana-shaped liquid-crystal molecules and assemble into ordered structures with a typical smectic B2 phase. The bent silica rods could serve as a visualizable mesoscopic model for exploiting the phase behaviors of bent molecules which represent a typical class of liquid-crystal molecules.
Co-reporter: Kun Liu;Ariella Lukach;Kouta Sugikawa;Siyon Chung;Dr. Jemma Vickery;Dr. Heloise Therien-Aubin; Bai Yang; Michael Rubinstein; Eugenia Kumacheva
Angewandte Chemie International Edition 2014 Volume 53( Issue 10) pp:
Publication Date(Web):
DOI:10.1002/anie.201401078
Co-reporter: Kun Liu;Ariella Lukach;Kouta Sugikawa;Siyon Chung;Dr. Jemma Vickery;Dr. Heloise Therien-Aubin; Bai Yang; Michael Rubinstein; Eugenia Kumacheva
Angewandte Chemie 2014 Volume 126( Issue 10) pp:2686-2691
Publication Date(Web):
DOI:10.1002/ange.201309718
Abstract
The resemblance between colloidal and molecular polymerization reactions is very useful in fundamental studies of polymerization reactions, as well as in the development of new nanoscale systems with desired properties. Future applications of colloidal polymers will require nanoparticle ensembles with a high degree of complexity that can be realized by hetero-assembly of NPs with different dimensions, shapes, and compositions. A method has been developed to apply strategies from molecular copolymerization to the co-assembly of gold nanorods with different dimensions into random and block copolymer structures (plasmonic copolymers). The approach was extended to the co-assembly of random copolymers of gold and palladium nanorods. A kinetic model validated and further expanded the kinetic theories developed for molecular copolymerization reactions.
Co-reporter: Kun Liu;Ariella Lukach;Kouta Sugikawa;Siyon Chung;Dr. Jemma Vickery;Dr. Heloise Therien-Aubin; Bai Yang; Michael Rubinstein; Eugenia Kumacheva
Angewandte Chemie 2014 Volume 126( Issue 10) pp:
Publication Date(Web):
DOI:10.1002/ange.201401078
Co-reporter: Kun Liu;Ariella Lukach;Kouta Sugikawa;Siyon Chung;Dr. Jemma Vickery;Dr. Heloise Therien-Aubin; Bai Yang; Michael Rubinstein; Eugenia Kumacheva
Angewandte Chemie International Edition 2014 Volume 53( Issue 10) pp:2648-2653
Publication Date(Web):
DOI:10.1002/anie.201309718
Abstract
The resemblance between colloidal and molecular polymerization reactions is very useful in fundamental studies of polymerization reactions, as well as in the development of new nanoscale systems with desired properties. Future applications of colloidal polymers will require nanoparticle ensembles with a high degree of complexity that can be realized by hetero-assembly of NPs with different dimensions, shapes, and compositions. A method has been developed to apply strategies from molecular copolymerization to the co-assembly of gold nanorods with different dimensions into random and block copolymer structures (plasmonic copolymers). The approach was extended to the co-assembly of random copolymers of gold and palladium nanorods. A kinetic model validated and further expanded the kinetic theories developed for molecular copolymerization reactions.
Co-reporter:Kun Liu, Aftab Ahmed, Siyon Chung, Kota Sugikawa, Gaoxiang Wu, Zhihong Nie, Reuven Gordon, and Eugenia Kumacheva
ACS Nano 2013 Volume 7(Issue 7) pp:5901
Publication Date(Web):June 20, 2013
DOI:10.1021/nn402363p
Self-assembly of gold nanorods (NRs) in linear, polymer-like chains offers the ability to test and validate theoretical models of molecular polymerization. Practically, NR chains show multiple promising applications in sensing of chemical and biological species. Both areas of research can strongly benefit from the development of a quantitative tool for characterization of the structure of NR chains in the course of self-assembly, based on the change in ensemble-averaged optical properties of plasmonic polymers; however, quantitative correlation between the extinction spectra and the structural characteristics of NR chains has not been reported. Here, we report such a tool by a quantitatively correlating the red shift of the longitudinal surface plasmon band of gold NRs and the average aggregation number of NR chains. The generality of the method is demonstrated for NRs with different aspect ratios, for varying inter-rod distances in the chains, and for varying initial concentrations of NRs in solution. We modeled the extinction spectra of the NR chains by combining the theory of step-growth polymerization with finite-difference time-domain simulations and a resistor-inductor-capacitor model, and obtained agreement between the theoretical and experimental results. In addition to capturing quantitatively the ensemble physics of the polymerization, the proposed ‘plasmonic counter’ approach provides a real-time cost- and labor-efficient method for the characterization of self-assembly of plasmonic polymers.Keywords: aggregation number; extinction spectra; gold nanorods; plasmonic polymers; self-assembly; simulations
