Rational Design and Fabrication of Noble‐metal‐free NixP Cocatalyst Embedded 3D N‐TiO2/g‐C3N4 Heterojunctions with Enhanced Photocatalytic Hydrogen Evolution

Abstract

AbstractDeveloping low‐cost and efficient noble‐metal‐free photocatalytic materials is crucial for the hydrogen production through water splitting. Herein, N‐TiO2/g‐C3N4 heterostructure loaded with a noble‐metal‐free NixP cocatalyst was prepared by the combination of ammonia etching and photo‐reduction deposition method. The results demonstrated that N‐doped TiO2 (N‐TiO2) nanosheets were formed and stood upright on the surfaces of g‐C3N4 nanosheets, forming a 3D structure. The ternary hybridization of N‐TiO2/g‐C3N4@NixP hierarchical nanostructure was a promising strategy to achieve highly efficient photocatalytic H2 evolution, showing an optimized hydrogen evolution rate of 5438 μmol g−1⋅h−1 using 300 W Xe lamp as irradiation source, which was 7.5 times higher than that of N‐TiO2/g‐C3N4. The enhanced photocatalytic activity was ascribed to the combined effects of NixP cocatalyst loading and the formation of the intimate nanoheterojunctions between TiO2 nanosheets and g‐C3N4 nanosheets, which were favorable for promoting charge transfer. The present work would provide a novel facile preparation and practical application of many other noble‐metal‐free metal phosphides as a highly efficient cocatalyst for hydrogen production through water splitting.