TiO2 modified g-C3N4 with enhanced photocatalytic CO2 reduction performance.

Titanium dioxide (TiO 2) modified g-C 3 N 4 for composite photocatalysts were fabricated by using ball-milling and calcination. The physicochemical properties of as-obtained photocatalysts were characterized by XRD, XPS, SEM, TEM, UV–vis DRS, PL and Photocurrents. The results show that the heterostructure successfully formed between TiO 2 and C 3 N 4 , and the heterostructure could effectively enhance the separation rate of the photogenerated electrons and holes. Also the positions of conduction band (CB) and valence band (VB) changed with improving the amount of TiO 2 in the as-prepared photocatalysts. The photocatalytic activities of as-prepared photocatalysts were investigated by photoreduction of CO 2 , the results exhibit that the composite photocatalysts clearly improve the photoreduction of CO 2 to CH 4 and CO. The highest yields of CH 4 and CO are of 72.2 and 56.2 μmol g−1 at an optimized modified amounts of TiO 2 under 4 h irradiation of 8 W UV lamp, respectively. The strategy of TiO 2 modified C 3 N 4 could successfully obtain effective photocatalyst for CO 2 conversion. Image 1056065 • TiO 2 modified g-C 3 N 4 composite photocatalysts were fabricated by using ball-milling method and calcination. • The positions of conduction band (CB) and valence band (VB) changed with improving the amount of TiO 2 in the composite photocatalysts. • The composite photocatalysts clearly improve the photoreduction of CO 2 to CH 4 and CO. [ABSTRACT FROM AUTHOR]