Metal chalcogenide-based cathodes are crucial for the development of rechargeable magnesium batteries, yet the strong electrostatic interactions of Mg²⁺ result in slow ion transport and high polarization. The Mg²⁺/Li⁺ hybrid battery holds promise for enhancing the energy storage capability. Herein, we establish a system that utilizes (Co,Cu)Se₂/CoSe_x heterostructure grown on carbon cloth as the cathode and APC-LiCl as a dual-salt electrolyte to achieve high reversible capacity, enhanced cyclic stability, and impressive rate performance. First-principles calculations and kinetic analyses are employed to uncover that constructing the heterointerface stimulates the formation of an intrinsic electric field and high-density electron flows, thereby accelerating charge transfer and ion diffusion processes. Finite element simulations further demonstrate that the heterostructure effectively alleviates stresses associated with magnesiation/lithiation to enhance the structural integrity of the material. Moreover, the multistep reaction unveils a stepwise structural transformation pathway. This study initiates a new chapter in designing heterointerface strategies for advanced energy storage devices.

中文翻译：

---

工程异质界面协同调节铜钴硒化物对可逆镁/锂混合电池的动力学和应力


基于硫属化物的金属阴极对于可充电镁电池的开发至关重要，但 Mg²⁺ 的强静电相互作用导致离子传输缓慢和高极化。Mg²⁺/Li⁺ 混合动力电池有望增强储能能力。在此，我们建立了一个系统，利用在碳布上生长的 （Co，Cu）Se₂/CoSe_x 异质结构作为阴极，利用 APC-LiCl 作为双盐电解质，以实现高可逆容量、增强的循环稳定性和令人印象深刻的倍率性能。采用第一性原理计算和动力学分析来发现构建异质界面会刺激本征电场和高密度电子流的形成，从而加速电荷转移和离子扩散过程。有限元仿真进一步表明，异质结构有效减轻了与镁化/锂化相关的应力，从而增强了材料的结构完整性。此外，多步反应揭示了一步结构转变途径。本研究开启了为先进储能器件设计异质接口策略的新篇章。