Bimetal–Organic Framework-Derived Porous Rodlike Cobalt/Nickel Nitride for All-pH Value Electrochemical Hydrogen Evolution

Developing advanced hydrogen evolution reaction (HER) electrocatalysts is of great significance. Herein, we report porous rodlike cobalt-nickel bimetal nitrides (Co xNi yN) as high-efficiency HER electrocatalysts in a wide pH range through nitridation from a bimetal-organic framework (MOF-74) precursor. Thanks to collaborative superiorities of high surface areas, abundant mesoporous structure, perfect metal element dispersion, and electron modulation effect, the as-prepared Co xNi yN possess a superior catalytic ability toward HER at all pH values. In particular, the optimal Co2Ni1N requires overpotentials of 102.6 and 92.0 mV to afford a current density of 10 mA cm-2 in alkaline and acidic solution, respectively. In addition, it also presents favorable activity in neutral media and excellent stability under different pH conditions. The present study not only offers a strategy for the design and synthesis of porous bimetal nitrides derived from binuclear MOF but also brings up new avenues for the development of cost-effective and competent all-pH HER catalysts for renewable energy systems.