Enhanced photocatalytic water splitting hydrogen production on RuO2/La:NaTaO3 prepared by sol-gel method

摘要

Sodium tantalates NaTaO3 and La:NaTaO3 prepared by the sol-gel method and impregnated with triruthenium dodecarbonyl were studied as photocatalysts for water splitting. X-ray diffraction of the samples showed perovskite-type crystalline structure. Small particulate solids (<100 nm) were observed by SEM. Well dispersed RuO2 particles (<6nm) on the surface of the tantalates were observed by HRTEM. Hydrogen production of water irradiation with UV light source was 110 μmol h~(-1) and 155 μmol h~(-1) on NaTaO3 and La:NaTaO3 photocatalysts, respectively. On RuO2/tantalates catalysts improved photoactivity was observed. Activities up to 4108 H2 μmol h~(-1) were obtained. The higher activity of the RuO2/tantalates was attributed to an important diminution in the electron-hole pair recombination due to the effect produced by the presence of La in the NaTaO3 structure as well as by the role of RuO2 like electron-trap.