Fractal to monolayer growth of AgCl and Ag/AgCl nanoparticles on vanadium oxides (VOx) for visible-light photocatalysis

Abstract

A facile and simple methodology was adopted for the trapping of highly crystalline AgCl and Ag/AgCl nanoparticles (NPs) into the interlayer spacings of vanadium oxides (VO_x). Self-organization of AgCl and Ag/AgCl-NPs on VO_x was found to be governed by the nature of the dicarboxylic acids used during the synthesis of the nanocomposites. A “fractal-like” morphology of the AgCl@VO_x nanocomposite was achieved in the presence of cis-1,2 cyclohexanedicarboxylic acid. Heating of the AgCl@VO_x nanocomposite above 68 °C resulted in the growth of polydispersed and ultrafine (3–4 nm) Ag/AgCl-NPs and its self-organization into monolayer formation on a partly crystalline VO_x matrix. Change in the conformation of the dicarboxylic acid to the trans-isomer resulted in the formation of a ‘rod-like’ structure of Ag/AgCl-NPs on a highly crystalline VO_x matrix. The band gaps of the nanocomposites were within the range of 1.8 to 2.9 eV. Because of such a low band gap, the synthesized nanocomposites were found to be highly active toward the photooxidation of methylene (MB) and methyl orange (MO) under sunlight.