MXene-derived C-doped TiO2/Ti3C2 heterojunction as a high-performance visible-light photocatalyst

Fabrication TiO 2 with conductive two-dimensional materials is an effective strategy to improve its photocatalytic activity. Herein, a well-defined carbon-doped TiO 2 /Ti 3 C 2 heterojunction is constructed via in situ controllable oxidation of Ti 3 C 2 MXene in carbon dioxide. The formed C-doped TiO 2 nanoparticles as the photocatalyst uniformly disperse on the surface of Ti 3 C 2 MXene and generate electrons and holes under irradiation. The two-dimensional Ti 3 C 2 MXene, owing to its excellent conductivity, acts as the electron transport channels and accelerates the separation of photogenerated electrons and holes. Meanwhile, due to its large specific surface area and good solubility, Ti 3 C 2 MXene may facilitate to enhance the adsorption of pollutant on the photocatalyst as well as the absorption of photocatalyst for visible light. Therefore, the unique merits of TiO 2 and Ti 3 C 2 MXene are integrated to deliver the composites high photocatalytic activity. The proper content of Ti 3 C 2 MXene and TiO 2 in the composite is crucial for enhancing the photocatalytic performance, which can be effectively tuned by varying the oxidation temperature. In this work, C-doped TiO 2 /Ti 3 C 2 oxidized at 400 °C presents the optimum photocatalytic performance.