Boosting Hydrogen Oxidation Performance of Phase-Engineered Ni Electrocatalyst under Alkaline Media

Exploring high-performance and stable Ni-based electrocatalyst toward the hydrogen oxidation reaction (HOR) under alkaline media is crucial for the development of alkaline exchange membrane fuel cells (AEMFCs). Herein, we demonstrate that a phase-engineered Ni electrocatalyst with the hexagonal-close-packed (hcp)/face-centered-cubic (fcc) interface can be adopted as a highly efficient and stable catalyst toward alkaline HOR Density functional theory (DFT) and experimental results indicate that the inter-regulated electronic structure and d-band center at the interface of hcp/fcc-Ni-C could lead to the optimized binding hcp-Ni fcc-Ni energy of H and OH species, which, together with the reduced formation energy of water species, contributes to the excellent HOR performance, with 6-fold higher mass activity than the conventional fcc-Ni electrocatalyst.

Automated summary

In this study, a phase-engineered Ni electrocatalyst is demonstrated to be highly efficient and stable for alkaline hydrogen oxidation reaction. The inter-regulated electronic structure and interface characteristics of the Ni catalyst contribute to the improved performance.