Direct Z‐Scheme Heterostructure of Nanoparticle‐CdSe on Nanorod‐NaNbO3: Facile Hydro‐thermal Construction and Superior Photocatalytic Activity and Stability in H2 Evolution

Abstract

The advancement of exceptionally effective catalysts that are photostable is significantly important for the sustainable conversion of solar energy into hydrogen. Combining the strengths of NaNbO3 and CdSe in a fabricated heterojunction has been pursued in photocatalysis to enhance the performance while addressing CdSe's stability. In this study, nanoparticle‐CdSe was deposited on NaNbO3 nanorods via hydrothermal method, and the optimal composite ratio of CdSe/NaNbO3 heterojunction achieved a photocatalytic hydrogen production of 2510 μmol g‐1h‐1. The enhancement is ascribed to the formation of a Z‐scheme heterojunction by the interface contact between CdSe and NaNbO3.The migration of electrons from NaNbO3 to CdSe was revealed by charge density difference results in DFT calculation. Work function of samples demonstrated the equilibrium of Fermi level and a corresponding shift of the band structure in the heterojunction. The H2 adsorption free energy (ΔGH*) for the heterojunction was 0.26 eV, suggesting a reduced energy barrier for hydrogen generation. Notably, the stable structure of NaNbO3 endows the composites with excellent chemical stability, maintaining more than 80% activity after six hydrogen production cyclic tests. This work offers valuable insights into the development of direct Z‐scheme structure catalysts for photocatalytic water splitting.