An Mn-doped NiCoP flower-like structure as a highly efficient electrocatalyst for hydrogen evolution reaction in acidic and alkaline solutions with long duration

Abstract

The exploration of efficient non-noble metal electrocatalysts for hydrogen evolution reaction has received considerable attention to replace commercial Pt catalyst. It is known that the cooperative coupling of appropriate non-noble metals exhibits excellent HER performance than a single component. Herein, an Mn-doped NiCoP flower-like electrocatalyst with self-assembled nanosheets on a nickel foam is synthesized via successive hydrothermal methods, followed by low temperature phosphidation. The as-synthesized Mn-NiCoP presents extraordinarily high catalytic activity and robust chemical stability towards the hydrogen evolution reaction in both acidic and alkaline electrolytes. Benefiting from the dual modulation of the morphology structure and chemical compositions, Mn-NiCoP/NF achieves a current density of 10 mA cm⁻² at a low overpotential of 37 mV for HER in a 0.5 M H₂SO₄ solution. Moreover, it only requires overpotentials of 67 mV and 142 mV to deliver current densities of 10 mA cm⁻² and 50 mA cm⁻² in a 1 M KOH solution, respectively. Remarkably, it holds enhanced stability in 1 M KOH, maintaining HER activity for at least 120 h with negligible overpotential decay. The highly efficient and stable Mn-NiCoP electrocatalyst is valuable in applications relevant to energy storage.