Ba-Modified LaTiO2N as an Efficient Visible Light Active Photocatalyst for Water Oxidation

LaTiO 2 N has been considered as one of the most promising photocatalysts for solar energy conversion. Nevertheless, it generally has a poor photocatalytic activity under normal conditions, probably linked to severe structural distortions and various types of defects within this compound. Herein, we modified LaTiO 2 N by introducing Ba into its A site, that is, La 0.8 Ba 0.2 TiO 2.2 N 0.8 . The presence of Ba at the A site of LaTiO 2 N not only relaxes the structural distortions but also effectively inhibits defect formation ( e.g. Ti 3+ species) in LaTiO 2 N. Moreover, surface hydrophilicity of LaTiO 2 N is also improved by Ba modification. Photoelectrochemical analysis suggests that charge separation and transferring situation are ameliorated in Ba-modified LaTiO 2 N, and the valence band edge position is positively shifted. These factors are likely the reasons for the improved photocatalytic activity of La 0.8 Ba 0.2 TiO 2.2 N 0.8 in water oxidation reactions.