Structurally disordered MoSe2 with rich 1T phase as a universal platform for enhanced photocatalytic hydrogen production

The improvement of surface reactivity in noble-metal-free cocatalysts is crucial for the development of efficient and cost-effective photocatalytic systems. However, the influence of crystallinity on catalytic efficacy has received limited attention. Herein, we report the utilization of structurally disordered MoSe 2 with abundant 1T phase as a versatile cocatalyst for photocatalytic hydrogen evolution. Using MoSe 2 /carbon nitride (CN) hybrids as a case study, it is demonstrated that amorphous MoSe 2 significantly enhances the hydrogen evolution rate of CN, achieving up to 11.37 μmol h −1 , surpassing both low crystallinity (8.24 μmol h −1 ) and high crystallinity MoSe 2 (3.86 μmol h −1 ). Experimental analysis indicates that the disordered structure of amorphous MoSe 2 , characterized by coordination-unsaturated surface sites and a rich 1T phase with abundant active sites at the basal plane, predominantly facilitates the conversion of surface-bound protons to hydrogen. Conversely, the heightened charge transfer capacity of the highly crystalline counterpart plays a minor role in enhancing practical catalytic performance. This approach is applicable for enhancing the photocatalytic hydrogen evolution performance of various semiconducting photocatalysts, including CdS, TiO 2 , and ZnIn 2 S 4 , thereby offering novel insights into the advancement of high-performance non-precious catalysts through phase engineering.