Chalcogen‐Doping Engineered Electronic Reconstruction of Cu ₂ O@Cu Cathode Toward High‐Performance Cu–Zn Batteries

High‐performance cathode materials are a key to promoting the development of aqueous zinc‐based batteries (AZBs). In this work, we introduce two advanced chalcogen (Se, Te)‐doped Cu ₂ O@Cu cathodes synthesized through a simple two‐step hydrothermal method. Structural and electronic characterization combined with density functional theory (DFT) calculations demonstrate that doping with Se or Te in Cu ₂ O and Cu ⁰ leads to a rearrangement of the electronic structure in Cu ₂ O@Cu. The effect significantly enhances the OH ⁻ adsorption energy, charge transfer kinetics, activity, and stability of Cu ₂ O@Cu. Electrochemical results indicate that the optimal Se‐Cu ₂ O@Cu and Te‐Cu ₂ O@Cu electrodes achieve ultra‐high specific capacities of 32.6 mAh cm ⁻² (549.8 mAh g ⁻¹ ) and 28.47 mAh cm ⁻² (462.9 mAh g ⁻¹ ), respectively, along with remarkable cycling stability (exceeding 1000 cycles), outperforming undoped Cu ₂ O@Cu (7.81 mAh cm ⁻² , 134.2 mAh g ⁻¹ , 150 cycles). When assembled into Cu//Zn batteries by coupling with a metallic zinc anode, the Se–Cu ₂ O@Cu//Zn and Te–Cu ₂ O@Cu//Zn batteries deliver high energy densities of 9.59 and 12.76 mWh cm ⁻² , respectively, which outperform most existing aqueous battery systems. This study offers fundamental insights into the role of Se (Te) doping in Cu ₂ O@Cu electrodes and proposes an effective strategy for designing high‐performance copper‐based cathodes for AZBs.