Alkaline hydrogen oxidation reaction on nickel-based non-noble metal electrocatalysts

The anion exchange membrane fuel cell (AEMFC) enables the use of non-noble metal catalysts, greatly reducing the cost of fuel cells. Nickel-based materials are considered the most promising anode catalysts for practical applications in low-cost AEMFCs, but designing Ni-based catalysts with breakthrough performance remains a major challenge due to the slow kinetics of the anodic hydrogen oxidation reaction (HOR) in alkaline media. In this review, the electrocatalytic mechanisms of the alkaline HOR and the rigorous methods for assessing the performance of Ni-based catalysts are presented as the cornerstones for designing Ni-based catalysts. Alignment with the modulated geometric and electronic properties of Ni-based catalysts is thoroughly discussed, based on the principles of mechanism and performance evaluation. An element navigation map is presented to guide the precise design of efficient Ni-based non-noble metal catalysts for the alkaline HOR, and the current challenges and future prospects are outlined to provide valuable directions for new research about the alkaline HOR on Ni. This review not only offers insights into the rational design of Ni-based electrocatalysts but also provides a blueprint for the commercialization of cost-effective AEMFCs.