Electroless deposition of RuO2-based nanoparticles for energy conversion applications

Abstract

This study reports a delicate electroless approach for the deposition of RuO2 center dot nH(2)O nanoparticles on the VOx center dot mH(2)O nanowires and this method can be extended to deposit RuO2 center dot nH(2)O nanoparticles on various material surfaces. Electrochemical characterizations, including linear sweep voltammetry (LSV), electrochemical quartz crystal microbalance (QCM) analysis and rotating ring-disc electrode (RRDE) voltammetry, were carried out to investigate the growth mechanism. The deposition involves the catalytic reduction of dissolved oxygen by the V4+ species of VOx center dot mH(2)O, which drives the oxidation of RuCl3 to proceed with the growth of RuO2 center dot nH(2)O. This core/shell VOx center dot mH(2)O/RuO2 center dot nH(2)O shows a better catalytic activity of the oxygen reduction reaction (ORR) than RuO2 center dot nH(2)O, which is ascribed to the pronounced dispersion of RuO2 center dot nH(2)O. Such an electroless approach was applicable to the preparation of a RuO2-based nanoparticle suspension as well as the deposition of nanocrystalline RuO2 center dot nH(2)O on other functional supports like TiO2 nanowires. The thus-obtained RuO2-decorated TiO2 nanorods exhibit significantly an enhanced photoactivity toward photoelectrochemical water oxidation. The versatility of the current electroless approach may facilitate the widespread deployment of nanocrystalline RuO2 center dot nH(2)O in a variety of energy-related applications.