Abstract: To enhance the structural stability and electron/ion transport kinetics of high-entropy oxide (HEO) anode materials, a spinel-type (Cr0.2Fe0.2Mn0.2Ni0.2Zn0.2)3O4 HEO is employed as the representative model system. The anionic S-doping strategy is carefully implemented to precisely modulate intrinsic defects and microstructures. A series of mesoporous spinel-type (Cr0.2Fe0.2Mn0.2Ni0.2Zn0.2)3O4-xSx (x=0, 0.15, 0.3, 0.6, 0.9) HEOs with controllable oxygen vacancies, lattice distortion, and interconnected mesoporous frameworks are successfully synthesized via a solution-combustion route using metal nitrates, thiourea, and glycine as metal precursors, sulfur precursor, and fuel, respectively. The optimized (Cr0.2Fe0.2Mn0.2Ni0.2Zn0.2)3O3.7S0.3 (S0.3) electrode delivers a high reversible discharge capacity of 1513 mAh/g after 150 cycles at 200 mA/g, and retains 310 mAh/g after 350 cycles at 1000 mA/g, surpassing most of the previously reported HEO anodes. The superior cycling stability and rate capability arise from two key factors: on the one hand, moderate S2- incorporation increases configurational entropy, mitigates lattice distortion and regulates oxygen vacancy content, collectively ensuring structural integrity during prolonged cycling. The introduction of high configurational entropy combined with defect engineering stabilizes the crystal framework under prolonged cycling while activating redox centers more efficiently, this cooperative effect also minimizes irreversible structural degradation, thereby extending the operational lifespan of the electrode under practical high-rate conditions. On the other hand, synergistic optimization of lattice distortion, oxygen vacancies, and grain size markedly promotes electron/ion transport (S0.3 exhibits the highest electrical conductivity of 22.4 S/m and a relatively large Li+ diffusion coefficient), thereby effectively enhancing the pseudocapacitive contribution. This work demonstrates an effective anion-doping strategy for concurrently optimizing structural stability, electronic conductivity, and ionic mobility in HEOs, while providing an innovative and practical design concept along with a solid experimental foundation for lithium-ion battery anodes with high energy density and long cycling life.

Key words: lithium-ion batteries, spinel high-entropy oxides, anion dope, lattice distortion, oxygen vacancy, lithium storage performance

摘要： 为了进一步提升高熵氧化物负极材料的结构稳定性及电子/离子传输动力学，本研究以尖晶石型(Cr0.2Fe0.2Mn0.2Ni0.2Zn0.2)3O4高熵氧化物为研究基础，采用溶液燃烧法，通过S2-阴离子掺杂策略调控其本征缺陷与微观结构，成功制备了具有可控氧空位和晶格畸变及介孔网状结构的尖晶石型(Cr0.2Fe0.2Mn0.2Ni0.2Zn0.2)3O4-xSx (x=0, 0.15, 0.3, 0.6, 0.9)高熵氧化物锂离子电池负极材料。电化学测试结果表明，(Cr0.2Fe0.2Mn0.2Ni0.2Zn0.2)3O3.7S0.3 (S0.3)电极展示了优异的循环稳定性和倍率性能，在200 mA/g下循环150圈后可保持1513 mAh/g的可逆放电比容量，在1000 mA/g下循环350圈后仍具有310 mAh/g的放电比容量。其优异的电化学性能主要归因于：一方面，适量S2-掺杂不仅增加构型熵，还能缓解晶格畸变并降低氧空位浓度，从而显著提升电极材料的循环稳定性；另一方面，晶格畸变、氧空位与晶粒尺寸的协同优化显著改善电子/离子传输(S0.3的电导率高达22.4 S/m，且DLi?较大)并有效提升赝电容贡献率。本研究为兼具结构稳定性、高能量密度与长循环寿命的锂离子电池负极材料设计提供了新思路与实验基础。

关键词: 锂离子电池, 尖晶石型高熵氧化物, 阴离子掺杂, 晶格畸变, 氧空位, 储锂性能