Photon-thermal synergy for efficient solar H2 production by Ni-doped Zn0.7Cd0.3S

Developing advanced photothermal effect photocatalysts to maximize solar utilization receives increasing attentions in photocatalytic H 2 production. Herein, a Ni-doped Zn 0.7 Cd 0.3 S (Ni-ZCS-20) integrating photothermal material and photocatalyst was constructed via simple one-step hydrothermal method. Successful incorporation of Ni into Zn 0.7 Cd 0.3 S was confirmed by various characterization techniques including XRD, XPS, SEM and TEM. Under photothermal-assisted condition, the Ni-ZCS-20 offered a superfast H 2 generation rate, reaching as high as 183 mmol/g·h, which exhibited enormous advantages over existing photocatalysts. Detailed mechanism explorations verified that such a high H 2 generation rate of Ni-ZCS-20 could be attributed to the lowed H 2 generation overpotential, broadened light absorption region, and promoted photogenerated carrier separation originating from the Ni doping. In addition, the doped Ni partly substituted the Zn in Ni-ZCS-20, providing an extra channel for photogenerated electrons and efficiently hindering the recombination of electron-hole pairs. Density functional theory (DFT) calculations demonstrated that Ni incorporation into ZCS effectively tailored its electronic structure, enhanced surface electron-supply capability, and optimized hydrogen adsorption, thereby leading to superior catalytic performance of Ni-ZCS toward HER. This finding provides valuable guidance for constructing photothermal effect materials to exploit full spectrum solar in photocatalytic H 2 evolution.