Interfacial component coupling effects towards precise heterostructure design for efficient electrocatalytic water splitting

Electrocatalytic water splitting is an appealing method for generating renewable hydrogen. In acidic media, noble metals are commonly used as electrocatalysts, whereas in alkaline media, non-noble metals are used. However, due to the high cost and rarity of noble metals, as well as the low activity and stability of non-noble metals, industrial uses are severely constrained. Heterostructures are a possible alternative to costly electrocatalysts because of their tunable properties. The origin of activity and stability of heterostructures lies in the coupling between their constituent components. Thus, the establishment of interfacial component coupling effects such as the Mott-Schottky effect, the Strong-Metal-Support-Interaction effect, the support-stabilizing effect, and the synergistic effect is a promising technique for enhancing activity and stability. However, a lack of the generation rules for the interfacial coupling effects impedes their widespread application for the rational design. This review summarizes the progress made towards heterostructure design from the interfacial component coupling effects with respect to the various components. The challenges and future prospective have also been presented for the heterostructure electrocatalyst design. The findings reported in this review pave a way for the heterostructure electrocatalyst design for water splitting as well as other electrocatalytic processes such as oxygen reduction, CO2 reduction, nitrogen reduction reactions, etc.