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

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 (< 6 nm) 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.

Graphical AbstractActivities up to 4108 H2 µmolh–1 are obtained on water splitting using 1 wt.% RuO2/La:NaTaO3 as catalysts under UV irradiation.Figure optionsDownload as PowerPoint slideResearch Highlights
► Impregnation of Ru on sol–gel La:NaTaO3 enhances its activity for water splitting reaction.
► Activities up to 4108 H2 μmol h− 1 are obtained using 1 wt.% RuO2/La:NaTaO3.
► RuO2 and La in RuO2/La:NaTaO3 catalyst act as electron-trap of the excited electrons.
► RuO2/La:NaTaO3 catalyst activity is 25 times greater than that obtained with La:NaTaO3.