Photocatalytic activities for water decomposition of RuO2-loaded AInO2 (A = Li, Na) with d10 configuration

The photocatalytic activities for water decomposition of RuO2-loaded alkaline metal indates,AInO(2) (A=Li,Na), with d(10) configuration were studied. Under Hg-Xe lamp illumination, RuO2-loaded LiInO2 had little activity, but RuO2-loaded NaInO2 showed the ability to photocatalytically decompose water to hydrogen and oxygen. The photocatalytic activity strongly depended on the calcination temperature of NaInO2 with increasing calcination temperature, the activity increased, passed through a maximum, and sharply decreased. In case that a part of Na ion in NaInO2 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 (DIFT) was employed to elucidate the band structure of AInO(2) (A = Li, Na). The photocatalytic activities were compared with those of previously reported RuO2-loaded MIn2O4 (M = Ca, Sr), and the activity differences among them are discussed. (C) 2003 Elsevier Science B.V. All rights reserved.