Tungsten-doped MoS2-based nanostructure for photocatalytic hydrogen evolution under visible light

In this work, we introduced a simple approach to boost the photocatalytic activity of MoS₂ by introducing transition metal (W) doping. The W-MoS₂ (10 mg) exhibited a substantial enhancement in photocatalytic activity for H₂ production, achieving an impressive rate of approximately 925 µmol g⁻¹ after 6 h, which is 1.5-fold higher than bare MoS₂. The highest H₂ production activity of 1740 µmol g⁻¹ after 6 h was obtained for 50 mg W-MoS₂ photocatalyst. The observed increase in activity can be ascribed to the formation of a Schottky barrier at the heterojunction interface, along with advantageous properties of improved active sites resulting from tungsten doping into MoS₂. Furthermore, the enhanced activity of W-MoS₂ may be attributed to the promotion of catalytic kinetics by tungsten and molybdenum sites, exhibiting commendable activity for water dissociation and higher efficiency in H⁺ adsorption. These factors contribute significantly to the overall improved performance of the W-MoS₂ photocatalyst. Further, platinum (Pt) was also used as cocatalyst and enhanced photocatalytic activity of 2145 µmol g⁻¹ after 6 h was observed for W-MoS₂ + 5 wt% Pt.