Applications of Nickel‐Based Electrocatalysts for Hydrogen Evolution Reaction

The desire to exploit clean and sustainable energy sources with high gravimetric energy density has greatly inspired the exploration of hydrogen energy as an affordable alternative to fossil energy. Electrocatalytic water splitting is an efficient method for the low‐cost production of pure H 2 , but the use of platinum (Pt)‐like active electrocatalysts for the hydrogen evolution reaction (HER) remains necessary. In attempts to replace high‐value, scarce Pt catalysts, nickel‐based materials are being developed, as earth‐abundant HER electrocatalysts. Recently, a number of advanced nickel (Ni)‐based catalysts have been developed by rational synthesis strategies, including morphology control, structure tailoring, and interface engineering, significantly improving the HER performance. This review summarizes recent achievements in the application of Ni‐based HER electrocatalysts and demonstrates the advantages of each category in enhancing the HER performance. The current progress in the theory of water evolution and various modern techniques for characterizing catalysts are also reviewed, along with the rational design of Ni‐based nanostructure catalysts. Finally, the challenges in the practical applications of Ni‐based HER catalysts are highlighted.