“…Recently, the idea of developing a multifunctional electrocatalyst derived from the unique combination of at least two active materials has been expected to be able to effectively overcome the issues mentioned above. − Such an approach can further reduce the effective loading of each active material and the complication of electrode fabrication, thereby efficiently extending the application scope of the catalyst and enabling it to be more economically viable. In particular, since two active metal materials are decreased in size from nano/clusters to a well-dispersed single atom (SA) state, there is an effective increase of the low-coordination metal sites having a fine-tuned electronic structure for selective drive-specific multielectron reactions with high catalytic properties, while potentially providing 100% site utilization. − In this context, dual SAs can provide two sites enabling independent binding energies toward each reactant in different catalytic reactions. − In addition, their specific assembly within the host material, whether in in-plane, bridged, or cofacial form, may also effectively improve selectivity for certain reactions. , Despite their superior electrocatalytic activities, it is difficult to achieve a controlled synthesis method to maintain high loading of individual metal atoms because of their low structural stability arising from high surface energy and weak interactions between SAs and supporting material. Usually, SA catalysts are favorably stabilized by coordination to heteroatom (N, P, and S)-doped nanocarbons, which are low cost, robust, and tunable. , However, the powder form of products requires a polymer binder to make an electrode, thus significantly reducing catalytic activities and stability.…”