Fabrication of directly 2D Z-scheme CuTiO3/g-C3N4 with high photocatalytic activities for CO2 reduction and hydrogen production.

Photocatalysts based on Z-scheme heterostructure have been extensively investigated for CO 2 reduction and hydrogen production, which solve the problem of high electron-hole pair complexation and low reduction and oxidation capacity in photocatalysts. Here, two-dimensional CuTiO 3 /g-C 3 N 4 (CTO/CN) photocatalysts with directly Z-scheme heterostructure are prepared by effective manipulation of different components of CuTiO 3 (CTO) nanoparticles on 2D (two-dimension) porous g-C 3 N 4 (CN) nanosheets via in-situ growing strategy. Benefited from the special electronic structure, it demonstrates that the 4.0 % CTO/CN sample has an excellent photocatalytic activity for the reduction of CO 2 to H 2 (at a speed of 19.56 μmol g−1 h−1) and CO (at a speed of 19.93 μmol g−1 h−1), which are upper than those of pure g-C 3 N 4 by 43.5 and 17.1 times, respectively. Furthermore, the 4.0 % CTO/CN sample exhibits utstanding performance in electrocatalytic hydrogen production. This synthetic strategy is useful for constructing a 2D Z-scheme heterostructure for applications in energy-related areas. Schematic diagram of electrochemical hydrogen precipitation and carbon dioxide reduction of CuTiO 3 /CN heterojunction composites prepared by in situ growth method. [Display omitted] • A series of CuTiO 3 /g-C 3 N 4 nanosheets were prepared by applying in situ growth method. • CuTiO 3 /g-C 3 N 4 exhibits excellent performance for CO 2 reduction under visible light irradiation. • The 4.0 % CTO/CN had excellent electrochemical stability performance under neutral conditions. [ABSTRACT FROM AUTHOR]