Bifunctional CdS@Co8S9/Ni3S2 Catalyst for Efficient Electrocatalytic- and Photo-Assisted Electrocatalytic- Overall Water Splitting
Driving by electric or solar energy conversation to receive green hydrogen energy from water splitting is of great interest in nowadays. The development of highly efficient, stable, and noble-metal-free bifunctional electrocatalysts has sparked a huge investigation surge in the field of electrocatalytic (EC) water splitting. Herein, an original 1D core@2D branch CdS@Co8S9/Ni3S2 electrode is in-situ prepared on Co/Ni foam through a simple one-pot hydrothermal process. The binder-free, self-supported CdS@ Co8S9/Ni3S2 is demonstrated to be a low-cost and highly efficient bifunctional electrocatalyst for both hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) in alkaline solution. The optimal CdS@Co8S9/Ni3S2 electrode exhibit excellent bifunctional HER and OER properties with quite low overpotential of 69.6 mV and 285 mV to reach the EC current of -10 mA cm-2 and 20 mA cm-2, respectively. Moreover, using CdS@Co8S9/Ni3S2 electrode as both anode and cathode, the assembled electrolyzer only require a 1.56 V cell voltage to reach a current density of 10 mA cm-2. Significantly, it is also found that such metal-foam supported photocatalysts/electrocatalysts electrode can effectively realize a dual-model-incorporated photo-assisted electrocatalytic overall water splitting, which delivers a 174.1% higher H2 production rate than that of sole electrocatalysis. This work may open a new avenue for synergistic using solar energy and electric energy in the application of hydrogen production from water splitting.