Unlock the Visible-Light Photocatalytic OWS by Surface Disorder-Engineered Bi-Based Composite Oxides through Phosphorization.

It has been proven that the introduction of disorder in the surface layers can narrow the energy band gap of semiconductors. Disordering the surface's atomic arrangement is primarily achieved through hydrogenation reduction. In this work, we propose a new approach to achieve visible-light absorption through surface phosphorization, simultaneously raising the energy band structure. In particular, the surface phosphorization of Bi x Y 1- x VO 4 was successfully prepared by annealing them with a small amount of NaH 2 PO 2 under a N 2 atmosphere. After this treatment, the obtained Bi x Y 1- x VO 4 showed distinct absorption in visible light. The surface phosphorization treatment not only improves the photocatalytic activity of Bi x Y 1- x VO 4 but also enables visible-light photocatalytic overall water splitting. Furthermore, we demonstrate that this surface phosphorization method is universal for Bi-based composite oxides.