De, G and Kundu, D (2001) Gold-nanocluster-doped inorganic-organic hybrid coatings on polycarbonate and isolation of shaped gold microcrystals from the coating sol. Chemistry of Materials, 13 (11). 4239 -4246. ISSN 0897-4756

PDF - Published Version Restricted to Registered users only Download (319Kb) | Request a copy

Abstract

Au-nanocluster-doped inorganic-organic hybrid coatings on polycarbonate substrates were prepared for the application of abrasion-resistant colored coatings as well as nonlinear optical material. The Au-doped sol was prepared by incorporating HAuCl(4)(.)4H(2)O into a composite sol derived from 3-(glycidoxypropyl)trimethoxysilane, tetraethylorthosilicate, and 3-(methacryloxypropyl)trimethoxysilane via hydrolysis-condensation and epoxy polymerization reactions. When the coated substrates were exposed under UV light, three reactions occurred simultaneously: (i) reduction of Au ions into metallic Au nanoclusters, (ii) polymerization of methacrylate groups, and (iii) strengthening of the silica network. As a result, the UV-cured coatings became reddish-purple and more abrasion-resistant than the polycarbonate substrate. W-vis spectroscopy and TEM of the films showed a peak at 530 nm due to the surface plasmon resonance of Au nanoclusters and the presence of 8-10 nm spherical Au nanoclusters, respectively. XRD of the films also showed the characteristic peaks of metallic Au nanoclusters. The inorganic-organic hybrid network at the sol stage also acted as a new breeding medium for the generation of shaped (triangular, hexagonal, prismatic, etc.) Au microcrystals from the Au-doped sol without W irradiation. Electron diffraction suggests that these were single crystals with a preferential growth along the Au (111) plane.

Item Type:	Article
Subjects:	Processing Science
Divisions:	UNSPECIFIED
Depositing User:	Mrs Chandana Patra
Date Deposited:	10 Feb 2012 11:52
Last Modified:	20 Mar 2012 12:03
URI:	http://cgcri.csircentral.net/id/eprint/755

Actions (login required)

View Item