TiO2 modified with unique surface O-Zn-Cl species is prepared by a simple sol-gel method. The Zn modified TiO2 samples exhibit improved photocatalytic activity on photo-reduction of CO2 into CH4, compared with pure TiO2. The surface structure and photocatalytic properties are investigated by Raman, XRD, XPS, UV-vis absorption spectra, PL and time-resolved PL decay curves techniques. It is revealed that the existence of O-Zn-Cl species can extend the absorption into visible region, inhibit the recombination of charge carriers and prolong the lifetime of photogenerated electrons. Therefore the O-Zn-Cl modified TiO2 samples represent an improved photocatalytic performance on photo-reduction of CO2 into CH4. (C) 2016 Elsevier B.V. All rights reserved.