Modification of the Intermediate Binding Energies on Ni/Ni3N Heterostructure for Enhanced Alkaline Hydrogen Oxidation Reaction

Developing highly efficient and stable non-precious metal-based electrocatalysts for alkaline hydrogen oxidation reaction (HOR) is essential for the commercialization of alkaline exchange membrane fuel cells but remains a big challenge. Here, a simple strategy for constructing the Ni/Ni3N heterostructure electrocatalyst with remarkable catalytic performance toward HOR under alkaline electrolyte is reported. Density functional theory calculations and experimental results reveal that the inter-regulated d-band center of interfacial Ni and Ni3N derived from electron transfer from Ni to Ni3N across the interface can lead to the weakened hydrogen binding energy of Ni and strengthened hydroxyl binding energy of Ni3N, which, together with the decreased formation energy of water species, contributes to the outstanding HOR performance.

Automated summary

Developing highly efficient and stable non-precious metal-based electrocatalysts for alkaline hydrogen oxidation reaction (HOR) remains a big challenge for the commercialization of alkaline exchange membrane fuel cells. This study presents a simple strategy for constructing the Ni/Ni3N heterostructure electrocatalyst with remarkable catalytic performance under alkaline electrolyte. The inter-regulated d-band center of interfacial Ni and Ni3N derived from electron transfer across the interface plays a key role in achieving outstanding HOR performance.