Dual-Anion Doping Enables NiSe2 Electrocatalysts to Accelerate Alkaline Hydrogen Evolution Reaction

The quest for efficient electrocatalysts to accelerate hydrogen evolution reaction (HER) is of immense importance for global sustainability. Transition-metal-based selenides, especially NiSe2, are considered as one of the most promising HER catalysts due to their cost-effectiveness and superior conductivity, yet their inherent activity is poor. Herein, we reasonably designed and synthesized self-supported fluorine-phosphorus dual-anion co-doped NiSe2 nanosheets grown on carbon cloth (F/P-NiSe2/CC) with excellent HER performance. The obtained F/P-NiSe2 only requires low overpotentials of 53 and 137 mV to obtain current densities of 10 and 50 mA cm(-2), respectively, as well as a gentle Tafel slope of 95.6 mV dec(-1), and can sustain at least 120 h operation in alkaline media. Experimental analyses and density functional theory calculations have cross-proven that the electronic configuration of NiSe2 is successfully modulated by co-doping, which effectively improves the conductivity, optimizes hydrogen adsorption energy (Delta G(H*)), and makes it easier to get over the rate-limiting obstacle. This work not only reveals the relationship between the structure and properties of electrocatalysts under the dianion synergistic regulatory strategy but also enlightens the design of advanced electrocatalysts.