Sulfur Vacancy and Ti C T Cocatalyst Synergistically Boosting Interfacial Charge Transfer in 2D/2D Ti C T /ZnIn S Heterostructure for Enhanced Photocatalytic Hydrogen Evolution.

Constructing an efficient photoelectron transfer channel to promote the charge carrier separation is a great challenge for enhancing photocatalytic hydrogen evolution from water. In this work, an ultrathin 2D/2D Ti C T /ZnIn S heterostructure is rationally designed by coupling the ultrathin ZnIn S with few-layered Ti C T via the electrostatic self-assembly strategy. The 2D/2D Ti C T /ZnIn S heterostructure possesses larger contact area and strong electronic interaction to promote the charge carrier transfer at the interface, and the sulfur vacancy on the ZnIn S acting as the electron trap further enhances the separation of the photoinduced electrons and holes. As a consequence, the optimal 2D/2D Ti C T /ZnIn S composite exhibits a high photocatalytic hydrogen evolution rate of 148.4 µmol h , which is 3.6 times and 9.2 times higher than that of ZnIn S nanosheet and flower-like ZnIn S , respectively. Moreover, the stability of the ZnIn S is significantly improved after coupling with the few-layered Ti C T . The characterizations and density functional theory calculation demonstrate that the synergistic effect of the sulfur vacancy and Ti C T cocatalyst can greatly promote the electrons transfer from ZnIn S to Ti C T and the separation of photogenerated charge carriers, thus enhancing the photocatalytic hydrogen evolution from water.