Au adsorption and Au-mediated charge transfer on the SrO-termination of SrTiO3 (0Â 0Â 1) surface

► Au plays as electron trapping center on SrTiO3 (0 0 1) surface. ► Au mediates the charge transfer from electron-doped SrTiO3 to NO. ► Photogenerated electron-hole pairs can be effectively separated due to Au. ► Photocatalytic efficiency can be greatly improved due to Au adsorption.