Photocatalytic activities for water decomposition of RuO 2-loaded AInO 2 (A=Li, Na) with d 10 configuration

Abstract

The photocatalytic activities for water decomposition of RuO 2-loaded alkaline metal indates, AInO 2 (A=Li, Na), with d 10 configuration were studied. Under Hg–Xe lamp illumination, RuO 2-loaded LiInO 2 had little activity, but RuO 2-loaded NaInO 2 showed the ability to photocatalytically decompose water to hydrogen and oxygen. The photocatalytic activity strongly depended on the calcination temperature of NaInO 2: with increasing calcination temperature, the activity increased, passed through a maximum, and sharply decreased. In case that a part of Na ion in NaInO 2 was replaced by Li or K ion, the photocatalytic activity decreased sharply with a small amount of Li and gradually with increasing content of K. The calculation based on a plane wave density function theory (DFT) was employed to elucidate the band structure of AInO 2 (A=Li, Na). The photocatalytic activities were compared with those of previously reported RuO 2-loaded MIn 2O 4 (M=Ca, Sr), and the activity differences among them are discussed.