In situ-engineered coral-like multiphase NC@NiCoCu–N/NCF nanoarrays for enhanced hydrogen evolution reaction

Abstract

It is necessary to explore new energy sources to alleviate the excessive demand for fossil energy. Water electrolysis is a promising means of sustainable hydrogen evolution. Herein, a Cu/NCF precursor was nitrized to prepare a nitrogen-doped carbon-coated multi-component NC@NiCoCu-N/NCF composite material. The good synergistic interactions among the three nitride phases, Cu₃N, Ni₄N, and Co₂N, make H₂O decomposition and H₂ release more balanced during the reaction. The content and temperature were adjusted to explore the changes in the catalyst morphology and the trapezoidal nanosheets were transformed into a disordered rough coral-like nanostructure that facilitates better electrolyte penetration and provides more accessible active sites during the nitriding process. Nitrogen-doped carbon can enhance the conductivity of the catalyst, protecting the internal active structure from the erosion of the electrolyte and improving the structural stability. The NC@NiCoCu-N/NCF composite exhibited excellent hydrogen evolution performance and the overpotentials reached 89 mV and 131 mV under the current density of 10 mA cm⁻² in 1.0 M KOH and 0.5 M H₂SO₄, respectively. Chronopotentiometry results indicated that the catalyst could operate continuously for at least 48 h and still maintain excellent structural stability. This study has great significance for the development of polymetallic or multicomponent catalysts designed to accelerate the field of hydrogen energy.