Transition metal oxides are promising anode materials for lithium-ion batteries thanks to their good electrochemical reversibility, high theoretical capacities, high abundance, and low cost. The mechanism of lithium insertion or deintercalation into or from these metal oxides can be different depending upon their lattice structure or chemical nature. Synergistic effects obtained from mixing different metal oxides with (dis)similar lithiation/delithiation mechanisms (intercalation, conversion and alloying) can significantly improve the device performances. In this research, we systematically investigate the impact on electrochemical properties of SnO₂ thin-films upon mixing with TiO₂, Fe₂O₃ and ZnO. In these pure thin-films, SnO₂ displays conversion- as well as alloying-type lithiation and serves as the host material, whereas TiO₂ represents an intercalation-type anode material, Fe₂O₃ exhibits conversion reactions and ZnO expresses alloying during lithiation-delithiation processes. Importantly, all the composite thin-films have an intermixed structure at the atomic scale, as they are precisely prepared by the atomic layer deposition method. The electrochemical properties demonstrate that the composite thin-films show better performance, either higher capacities or better cycling retentions, than the individual constituent material (SnO₂, TiO₂, Fe₂O₃ or ZnO). Overall cycling stability improves to a great extent along with a slight increase in capacity with the addition of TiO₂. The supplement of Fe₂O₃ in the SnO₂–Fe₂O₃ composite thin-films moderately improves both capacity and retention, while the SnO₂–ZnO composite electrodes demonstrate a good cyclability and stabilize at a relatively high capacity. The systematic investigation of synergistic effects on the different types (intercalation, conversion and alloying) of metal oxide composites is expected to provide guidance towards the development of composite anode materials for lithium-ion batteries.

过渡金属氧化物因其良好的电化学可逆性，高理论容量，高丰度和低成本而成为锂离子电池的有希望的负极材料。锂从这些金属氧化物中插入或脱嵌的机理可能有所不同，具体取决于其晶格结构或化学性质。通过将不同的金属氧化物与（不相似的）锂化/脱锂机理（嵌入，转化和合金化）混合而获得的协同效应可以显着改善器件性能。在这项研究中，我们系统地研究了与TiO ₂，Fe ₂ O ₃和ZnO混合对SnO ₂薄膜的电化学性能的影响。在这些纯薄膜中，SnO_图2显示了转化型以及合金化的锂化作用并用作主体材料，而TiO ₂代表了插层型阳极材料，Fe ₂ O ₃表现出转化反应，而ZnO在锂化-脱锂化过程中表达了合金化。重要的是，所有复合薄膜在原子尺度上都具有混合结构，因为它们是通过原子层沉积法精确制备的。电化学性质表明，复合薄膜比单个组成材料（SnO ₂，TiO ₂，Fe ₂ O _3）表现出更好的性能，更高的容量或更好的循环保持率。或ZnO）。通过添加TiO _2，总体循环稳定性得到了很大程度的改善，同时容量略有提高。Fe的补充₂ Ó ₃中的SnO ₂ -Fe ₂ ö ₃复合薄薄膜适度改善了容量和维持率，而的SnO ₂ -ZnO复合电极表现出良好的循环性能和在相对高的容量稳定。系统研究不同类型（嵌入，转化和合金化）金属氧化物复合材料的协同效应，有望为锂离子电池复合阳极材料的开发提供指导。