Recent Advances in Pt-Based Electrocatalysts for Hydrogen Evolution Reaction: Mechanistic Insights, Engineering Strategies, and Future Perspectives

The electrochemical water splitting method is considered to be a promising opportunity to generate sustainable hydrogen, yet the challenge of high costs and sustainability issues related to hydrogen evolution reaction (HER) catalysts, which are based on platinum, represents a weak point preventing adoption on a large-scale basis. The current review outlines trends and achievements on platinum-based HER electrocatalysts with a focus on the correlation of atomic structures, mechanisms of catalysis, engineering techniques, and practical performance. The focus of the study is the fact that mechanistic knowledge was integrated in combination with electronic structure control in order to analyze the efficiency of Pt and degradation pathways. The mechanisms of catalysis were the ground for the assessment of the platinum alloys, heterostructures, single-atom catalysts, nanocomposites, and advanced supports on the basis of energy of adsorption of hydrogen (ΔG_H*), electronic interactions, and metal-support interaction effects. One of the conclusions that could be drawn from the comparison is that appropriate alterations of platinum properties make it possible to decrease the amount of platinum needed to achieve ultralow overpotentials with a maximum value not exceeding 30 mV at the current of 10 mA cm −2 and at the same time increase the mass activity of the catalyst. The analysis of the challenges related to catalyst deterioration, large-scale production of electrocatalysts, and their application in practice are carried out. Finally, the article suggests future perspectives in developing low-Pt and economically feasible HER catalysts.