Novel NiCo 2 Se 4 /Mn 0.5 Cd 0.5 S photocatalyst for visible light-driven hydrogen evolution

The development of efficient and stable photocatalysts is one of the most important research directions to realize the practical application of photocatalytic hydrogen evolution. A series of novel visible light responsive NiCo 2 Se 4 /Mn 0.5 Cd 0.5 S composites with different NiCo 2 Se 4 contents were prepared by hydrothermal method. The composites were characterized using different characterization techniques such as XRD, SEM, TEM, XPS, UV–Vis DRS, PL, and photoelectrochemistry. Photocatalytic hydrogen evolution reaction was also performed using visible light (λ > 420 nm) in an aqueous solution containing Na 2 S·9H 2 O and Na 2 SO 3 as sacrificial reagents. The 4% NiCo 2 Se 4 / Mn 0.5 Cd 0.5 S composites exhibited the highest photocatalytic hydrogen evolution capacity, producing 20 mmol h −1 g −1 of hydrogen, higher than pure Mn 0.5 Cd 0.5 S (12.2 mmol h −1 g −1 ). The tight bonding of the two materials in the NiCo 2 Se 4 /Mn 0.5 Cd 0.5 S composites may enhance the photocatalytic activity to some extent. The possible mechanism was suggested by UV–Vis DRS and photoelectrochemical measurements. The obtained NiCo 2 Se 4 /Mn 0.5 Cd 0.5 S composites have excellent photocatalytic activity and good stability in photocatalytic hydrogen evolution, and have potential applications in the photocatalytic hydrogen evolution from water using solar energy.