Tuning electronic structure and photocatalytic properties by Ag incorporated on (0Â 0Â 1) surface of anatase TiO2

► The adsorbed Ag plays as an electron trapping center on TiO2 (0 0 1) surface. ► The adsorptional Ag can be responsible for the visible light absorption peak. ► The substitutional Ag can suppress the recombination of photo-generated carriers. ► The interstitial Ag can also act as electron trapping center. ► Ag can improve the photocatalytic efficiency of TiO2 (0 0 1) surface.