Engineering of geometrical configurations in dual-atom catalysts for electrocatalytic applications

Geometrical configurations play a crucial role in dual-atom catalysts (DACs) for electrocatalytic applications. Significant progress has been made to design DACs electrocatalysts with various geometrical configurations, but in-depth understanding the relationship between geometrical configurations and metal-metal interaction mechanisms for designing targeted DACs is still required. In this review, the recent progress in engineering of geometrical configurations of DACs is systematically summarized. Based on the polarity of geometrical configuration, DACs can be classified into two different types that are homonuclear and heteronuclear DACs. Furthermore, with regard to the geometrical configurations of the active sites, homonuclear DACs are identified into adjacent and bridged configurations, and heteronuclear DACs can be classified into adjacent, bridged, and separated configurations. Subsequently, metal-metal interactions in DACs with different geometrical configurations are introduced. Additionally, the applications of DACs in different electrocatalytic reactions are discussed, including the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER), and other catalysis. Finally, the future challenges and perspectives for advancements in DACs are highlighted. This review aims to provide inspiration for the design of highly efficient DACs towards energy related applications.