CuO and its gallium composites with various compositions are successfully fabricated by using a hydrothermal technique followed by calcination at 900 °C. The added Ga precursors formed oxides in the composites, such as Ga₂O₃, CuGa₂O₄ and Cu₄O₃, as confirmed through the X-ray diffraction patterns as well as the HRTEM and SAED patterns. Further HRTEM analysis also confirmed that Cu₄O₃ and CuGa₂O₄ phases reside on the surface of CuO in the composites with a CuO : Ga ratio of 90 : 10. The contents of various oxide phases varied when we increased the amount of Ga in the CuO composites. Changing the ratios of CuO and Ga precursors in the composites is quite effective in tailoring the sodium-ion storage behaviour of CuO. The resultant CuO/Ga composites exhibit remarkable electrochemical performance for sodium-ion batteries in terms of capacity, rate capability and cycling performance. The composite containing 90% CuO and 10% Cu/Ga oxides delivers the highest charge capacity of 661 mA h g⁻¹ at a current density of 0.07 A g⁻¹ with a capacity retention of 73.1% even after 500 cycles. The structure and morphology of the composite (90% CuO and 10% Cu/Ga oxides) was successfully retained after 500 cycles, which was confirmed through ex situ XRD, SEM and HRTEM analyses. The composite also exhibited remarkable rate capability in which it delivered 96 mA h g⁻¹ even at a high current density of 6.6 A g⁻¹. The enhanced electrochemical performances of CuO and its gallium composites are attributed to the presence of Cu₄O₃ and CuGa₂O₄ phases. The Cu₄O₃ phase is actively involved in the redox reaction and the CuGa₂O₄ phase stabilizes the CuO phase and buffers the volume expansion of CuO during cycling. The present approach eplores great opportunities for improving the electrochemical performance of oxide based anode materials for sodium-ion batteries.

中文翻译：

---

Ga2O3、CuGa2O4和Cu4O3相对CuO及其镓复合材料钠离子储存行为的影响

通过使用水热技术然后在900°C下煅烧成功地制备了具有各种成分的CuO及其镓复合材料。通过X射线衍射图以及HRTEM和SAED图证实，添加的Ga前体在复合材料中形成氧化物，例如Ga ₂ O ₃、CuGa ₂ O ₄和Cu ₄ O _{3 。}进一步的 HRTEM 分析也证实了 Cu ₄ O ₃和 CuGa ₂ O ₄相存在于复合材料中的 CuO 表面，CuO: Ga 比率为 90:10。当我们增加 CuO 复合材料中的 Ga 量时，各种氧化物相的含量会发生变化。改变复合材料中 CuO 和 Ga 前体的比例对于调整 CuO 的钠离子存储行为非常有效。所得的 CuO/Ga 复合材料在容量、倍率性能和循环性能方面对钠离子电池表现出显着的电化学性能。^{含有 90% CuO 和 10% Cu/Ga 氧化物的复合材料在 0.07 A g -1}的电流密度下提供 661 mA hg ^-1的最高充电容量即使在 500 次循环后，容量保持率仍为 73.1%。复合材料（90% CuO 和 10% Cu/Ga 氧化物）的结构和形态在 500 次循环后成功保留，这通过非原位XRD、SEM 和 HRTEM 分析得到证实。该复合材料还表现出卓越的倍率性能，即使在 6.6 A g ^-1的高电流密度下也能提供 96 mA hg ^-1的电流。CuO及其镓复合材料的电化学性能增强归因于Cu ₄ O ₃和CuGa ₂ O ₄相的存在。Cu ₄ O ₃相积极参与氧化还原反应，CuGa ₂O ₄相稳定CuO相并缓冲循环期间CuO的体积膨胀。本方法为改善钠离子电池氧化物基阳极材料的电化学性能提供了巨大的机会。