Cd0.5Zn0.5S/Ti3C2 MXene as a Schottky catalyst for highly efficient photocatalytic hydrogen evolution in seawater

Photocatalytic hydrogen evolution is a developing technology that addresses the urgent energy shortage, without greenhouse gas emissions. Despite tremendous efforts over the past decades, the achievement of high-efficiency hydrogen evolution rates for application in semiconductors remains very challenging because of various factors, which include low charge mobility, low light absorption, and high charge carrier recombination. Nowadays, the built-in electric field of metal-semiconductor Schottky junctions exhibits significant developments to overcome the aforementioned limitations because of the enhanced charge separation and transportation efficiency. However, noble metals are scarce and unaffordable to limit the applications. As a promising alternative, the Ti 3 C 2 nanosheets showed excellent metal conductivity which is fascinating. A new Cd 0.5 Zn 0.5 S/Ti 3 C 2 composite was fabricated as a non-noble metal-based Schottky junction photocatalyst with enhanced H 2 production performance. For a practical exploration, this study expands its application in the realistic environment of natural seawater, which is not only more in line with the sustainable concept but also greatly alleviates the issue of limited freshwater. At present, due to the complex composition of seawater, only a few studies focus on the H 2 production of seawater. Remarkably, based on the rational design of the Cd 0.5 Zn 0.5 S/Ti 3 C 2 Schottky catalyst, the observed H 2 production rate of 9.071 mmol g −1 h −1 is thirty-three times higher than that of traditional Pt assisted photocatalyst in seawater.