Boosting Aluminum Adsorption and Deposition on Single‐Atom Catalysts in Aqueous Aluminum‐Ion Battery

Abstract In the quest for sustainable energy storage technologies, lithium‐based batteries, despite their prominence, face limitations such as high costs, safety risks, and supply chain issues. This has propelled the exploration of alternative materials, with aqueous aluminum‐ion batteries (AAIBs) emerging as a promising candidate due to their high energy density, abundance, and cost‐effectiveness. However, the low equilibrium reduction potential of aluminum ions presents significant challenges, including hydrogen evolution and poor cyclability. Addressing these, the study pioneers the application of single‐atom catalysts (SACs) in AAIBs, leveraging their high atom utilization and stability to enhance aluminum deposition and suppress hydrogen evolution. Sn, In, Cu, and Ni SACs are evaluated through density functional theory analysis and experimental validation, with Sn SAC identified as the most effective. Subsequently, the Sn SAC based anode demonstrates enhanced performance, achieving stable cycling over 500 h at 0.5 mA cm⁻², significantly improved capacity retention (60 mAh g⁻¹@300 cycles), and rate performance (50 mAh g⁻¹@1 A g⁻¹) in full cell tests. This work underscores the potential of SACs in advancing AAIB technology and opens new pathways for energy storage solutions.