Wu Chen, Xia Yuandong, Song Kejing, Cao Yongda, Huang Chenzhi, Chen Jiayi, Wang Yuan, Xu Chunliu
Natural Gas Research Institute, PetroChina Southwest Oil & Gasfield Company, Chengdu 610213, China.
College of Chemical Engineering, Sichuan University, Chengdu 610065, China.
Nanomaterials (Basel). 2025 Jun 8;15(12):885. doi: 10.3390/nano15120885.
NaTiO (NTO), with low sodium insertion potential (~0.3 V vs. Na/Na) and potential for high-energy-density batteries, is regarded as one of the most promising anode materials for sodium-ion batteries (SIBs). However, its practical application is hindered by poor electronic conductivity, sluggish Na⁺ (de)intercalation kinetics, and interfacial instability, leading to inferior cycling stability, low initial Coulombic efficiency, and poor rate capability. In this work, micron-sized rod-like NTO and Al-doped NTO (NTO-Al) samples were synthesized via a one-step high-temperature solid-state method. Al doping slightly reduced the size of NTO microrods while introducing oxygen vacancies and generating Ti, thereby enhancing electronic conductivity and reducing ionic diffusion resistance. H-TPR confirms that doping activates lattice oxygen and promotes its participation in the reaction. The optimized NTO-Al0.03 electrode delivered a significantly improved initial charge capacity of 147.4 mA h g at 0.5 C, surpassing pristine NTO (124.7 mA h g). Moreover, it exhibited the best cycling stability (49.5% capacity retention after 100 cycles) and rate performance (36.3 mA h g at 2 C).
钠钛氧化物（NTO）具有较低的钠嵌入电位（相对于Na/Na约为0.3 V）以及应用于高能量密度电池的潜力，被视为钠离子电池（SIBs）最具前景的负极材料之一。然而，其实际应用受到电子导电性差、Na⁺（脱）嵌动力学迟缓以及界面不稳定性的阻碍，导致循环稳定性较差、初始库仑效率较低以及倍率性能不佳。在这项工作中，通过一步高温固态法合成了微米级棒状NTO和铝掺杂的NTO（NTO-Al）样品。铝掺杂略微减小了NTO微棒的尺寸，同时引入了氧空位并生成了Ti，从而提高了电子导电性并降低了离子扩散电阻。H-TPR证实掺杂激活了晶格氧并促进其参与反应。优化后的NTO-Al0.03电极在0.5 C下的初始充电容量显著提高，达到147.4 mA h g，超过了原始NTO（124.7 mA h g）。此外，它表现出最佳的循环稳定性（100次循环后容量保持率为49.5%）和倍率性能（在2 C下为36.3 mA h g）。
