TiO₂/Ti₃C₂/g-C₃N₄ ternary heterojunction for photocatalytic hydrogen evolution

Photocatalytic hydrogen (H₂) generation derived by water has been considered as a renewable energy to solve environmental problems and global energy crises. Thus, it is necessary to explore the most effective photocatalysts by using multi-cocatalysts, due to an intimate interaction between different components. Therefore, we already synthesized the TiO₂/Ti₃C₂/g-C₃N₄ (TTC) photocatalyst from g-C₃N₄ and Ti₃C₂ MXene via a calcination technique, and applied this composite for H₂ evolution. By making use of titanium atom from Ti₃C₂ MXene, titanium dioxide (TiO₂) was in-body developed, which leads to form a close heterostructure between metallic material and semiconductors. Besides, g-C₃N₄ amorphous with highly surface area also contributes to harvest light irradiation during photocatalytic activity. The optimized TTC-450 heterostructure showed a super H₂ generation efficiency than those of pure g-C₃N₄ and other samples. Besides, TTC-450 sample also exhibited great recyclability after 4 runs. The proposed mechanism illustrates the efficient movement of generated electrons in TTC system, which leads to high H₂ evolution efficiency. Moreover, the obtained results consistently emphasize the TiO₂/Ti₃C₂/g-C₃N₄ composite would be a unique material for H₂ production and broaden applications of MXene materials.