Highly Efficient Schottky Heterojunctions for Photocatalytic Hydrogen Evolution: Facile Synthesis of Hollow Nano-ZnSe Spheres on Ti3C2-Nanosheets.

Abstract

Traditional photocatalysts often have limited efficiency due to the high recombination rate of photogenerated electron-hole pairs. In this work, we synthesized 3D/2D ZnSe-MXene Schottky heterojunctions by an in situ electrostatic self-assembly method. Notably, the 3 % MXene-ZnSe composite exhibited an optimized photocatalytic hydrogen production rate of 765.0 μmol g^-1 h^-1, about 1.6 times higher than that of pristine ZnSe. MXene's high conductivity and large surface area enhance catalytic performance by providing more active sites and efficient electron transfer pathways from ZnSe to MXene. This accelerates the separation and movement of photogenerated carriers, significantly reducing recombination. We have investigated the photocatalytic hydrogen production mechanism of the ZnSe-MXene composites using various characterization techniques. Our findings provide favourable insights into the synergistic effects within the heterojunction, offering valuable guidance for the design and development of advanced photocatalytic materials.