One-step preparation of CdS nanocrystals supported on thiolated silica-gel matrix and evaluation of photocatalytic performance

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Here we report the use of a thiol-functionalized silica-gel to prepare supported CdS nanocrystals by a facile one-step procedure. Upon changing the relative proportion of the matrix we obtained nanocrystals with different average sizes and size distributions, as evidenced by spectroscopic measurements as well as TEM images. Photoluminescence spectra also indicated that the main effect of the matrix is related to the size control since the spectral profiles were found to be strongly dependent on the excitation wavelength. The performance of the material in the photocatalytic degradation of two commercial dyes (methylene blue and rhodamine 6G) has been tested under sunlight radiation, showing promising results. Almost complete decolorization has been observed after 80 min of exposure, with no adsorption on the silica surface. (C) 2011 Elsevier B.V. All rights reserved.203151157Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FapitecCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES