Constructing Defect-Mediated CdS/g-C3N4 by an In-situ Interlocking Strategy for Cocatalyst-free Photocatalytic H2 Production

The construction of heterojunction photocatalyst is an emerging strategy for realizing efficient photocatalytic hydrogen production, and the methodology of construction is critical for improving the interfacial charge carriers separation and transfer. A weakly coupling interface in a heterojunction leads to lower hydrogen production activity and stability. Herein, a facile strategy based on an in-situ interlocking reaction is developed to solve the interfacial contact issue. Litchi-like CdS is anchored at the defects of the g-C3N4 (CN) by an interlocking process, and the contact interface is further extended by some small necking CdS particles that assembled on the contact corner because of the surface tension. The as-formed CdS/g-C3N4 (CdS/CN) has a unique and strongly coupling interface, which can effectively improve interfacial separation and transfer kinetics of photogenerated charge carriers due to the synthetic advantages of interlocking binding, necking effect, and heterojunction. Impressively, the as-prepared CdS/CN photocatalyst yields over 36 folds of cocatalyst-free hydrogen generation rate than the pure CdS under the visible light irradiation. This work presents a case of practical study to realize the synthesis of defect-mediated heterojunction photocatalysts by a facile strategy.