Photocatalytic hydrogen production using novel noble-metal-free NiMo/ CdS photocatalysts with hollow nanospheres structure

The need for sustainable and renewable energy sources has led to a surge in study in the subject of photocatalytic hydrogen production, which offers a viable method of converting solar energy into clean hydrogen energy, and developing low-cost and highly active photocatalysts without noble metal elements is the key to achieving its practical applications. In this study, a noble-metal-free NiMo bimetallic cocatalyst loaded on CdS photocatalysts with hollow nanospheres structure (HNS-CdS) is constructed and synthesized, and its photocatalytic performance is evaluated. The SEM and TEM characterization results indicate that the NiMo bimetals were uniformly dispersed on the surface of CdS hollow nanospheres in the NiMo/HNS-CdS photocatalysts. And, it has been demonstrated that the NiMo bimetallic co-catalysts with synergistic effect significantly enhance the photocatalytic performance of HNS-CdS. The NiMo/HNS-CdS photocatalysts with 8 wt% NiMo bimetal content showed the best hydrogen evolution performance with a rate of up to 2523 mu mol/g/h, which is 28 and 6 times greater than that of pure HNS-CdS and Pt/HNS-CdS with noble metal Pt as cocatalysts. The electrochemical and spectral characterization results indicate that the enhanced photocatalytic performance can be attributed to the ability of NiMo bimetallic cocatalysts to speed photogenerated charges transfer and suppress their recombination in the novel noble-metal-free NiMo/HNS-CdS photocatalysts. This work shows a viable approach to the development of CdS-based photocatalysts with high performance by replacing noble metal Pt with noble-metal-free NiMo bimetals as co-catalysts.