Noble metal-free Mn0.2Cd0.8S/NiSe2 nanocomposites for efficient photothermal-assisted photocatalytic H2 evolution

Abstract

Photothermal-assisted photocatalytic H2 evolution has attracted increasing attention in solar energy-hydrogen energy conversion. Herein, a novel Mn0.2Cd0.8S/NiSe2 (MCS/NiSe2) nanocomposite heterojunction with photothermal and co-catalyst dual effects was constructed to boost visible-near-infrared (Vis-NIR) light-driven H2 evolution activity. MCS/NiSe2 nanocomposite could obtain increased light absorption intensity, affluent active reaction sites and enhanced charge separation efficiency because of the decoration of NiSe2 co-catalyst. Meanwhile, the photothermal effect of NiSe2 could raise reaction system temperature, thus further accelerating carriers transfer and surface reaction rate. Consequently, MCS/NiSe2 nanocomposite could obtain the highest H2 evolution rate of 22.5 mmol g−1 h−1 under Vis-NIR light irradiation, reaching 3.2 times of MCS. This work provides a novel idea for the rational design of efficient photocatalysts by making full utilization of the synergetic effects of co-catalyst modification and photothermal effect without external heating source.