Abstract Titanium dioxide (TiO2) modified g-C3N4 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 TiO2 and C3N4, 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 TiO2 in the as-prepared photocatalysts. The photocatalytic activities of as-prepared photocatalysts were investigated by photoreduction of CO2, the results exhibit that the composite photocatalysts clearly improve the photoreduction of CO2 to CH4 and CO. The highest yields of CH4 and CO are of 72.2 and 56.2 μmol g−1 at an optimized modified amounts of TiO2 under 4 h irradiation of 8 W UV lamp, respectively. The strategy of TiO2 modified C3N4 could successfully obtain effective photocatalyst for CO2 conversion.

中文翻译：

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具有增强的光催化 CO2 还原性能的 TiO2 改性 g-C3N4

摘要 采用球磨和煅烧方法制备了二氧化钛（TiO2）修饰的g-C3N4复合光催化剂。通过XRD、XPS、SEM、TEM、UV-vis DRS、PL和光电流对所获得的光催化剂的理化性质进行了表征。结果表明，TiO2与C3N4成功形成异质结构，异质结构能有效提高光生电子和空穴的分离率。导带（CB）和价带（VB）的位置也随着所制备的光催化剂中TiO2含量的增加而改变。通过光还原 CO2 研究了制备的光催化剂的光催化活性，结果表明复合光催化剂明显改善了 CO2 光还原为 CH4 和 CO。在优化的 TiO2 改性量下，在 8 W 紫外灯照射 4 小时后，CH4 和 CO 的最高产率分别为 72.2 和 56.2 μmol g-1。TiO2 改性C3N4 策略可以成功获得有效的CO2 转化光催化剂。