| 李鹏志,盛子墨,范哲,袁涛.In3+掺杂提升钠离子电池铁锰基 层状氧化物正极稳定性[J].有色金属材料与工程,2025,46(1):48-56. |
| In3+掺杂提升钠离子电池铁锰基 层状氧化物正极稳定性 |
| Enhancement of stability in iron-manganese layered oxide cathode for sodium-ion batteries via In3+ doping |
| |
| DOI：10.13258/j.cnki.nmme.20240312002 |
| 中文关键词: 钠离子电池 层状正极 O3型NaFe0.5Mn0.5O2 Jahn-Teller效应 In3+掺杂 |
| 英文关键词:sodium-ion batteries layered cathode O3-type NaFe0.5Mn0.5O2 Jahn-Teller effect In3+ doping |
| 基金项目:国家自然科学基金资助项目(22379096) |
|
| 摘要点击次数: 14 |
| 全文下载次数: 35 |
| 中文摘要: |
| O3型NaFe0.5Mn0.5O2由于成本低廉，是一种极具商业潜力的钠离子电池层状正极材料，但其循环稳定性不佳是商业化面临的主要挑战之一。在Na+脱嵌过程中，Mn3+的强烈Jahn-Teller效应引起的不可逆相变和过渡金属（transition metal，TM）离子迁移是容量衰减的主要原因。采用电化学惰性离子In3+取代Mn3+的研究发现：In3+掺杂通过调节TM离子的价态来抑制Jahn-Teller效应，从而增强结构稳定性；有效增强了TM―TM以及TM―O的键能，缩小了TM离子层间距，降低了TM离子迁移的可能性；减小了正极材料颗粒的粒径，缩短了Na+的传输距离，提高了离子的扩散能力。改性后的NaFe0.5Mn0.5-xInxO2样品在电压为2.0～4.0 V时表现出了更好的倍率性能和循环稳定性，可提供111.4 mA·h/g的可逆比容量。经过200圈循环后，其容量保持率从25.78%提升至93.62%。 |
| 英文摘要: |
| O3-type NaFe0.5Mn0.5O2, known for its cost-effectiveness, stands as a promising commercial layered cathode material for sodium-ion batteries. Nonetheless, its poor cycling stability is one of the main challenges in commercialization. The irreversible phase transition and transition metal (TM) ion migration, induced by the strong Jahn-Teller effect of Mn3+ during Na+ disembedding, are the main causes of capacity decay. The research that substituted Mn3+ with electrochemically inert In3+ found that In3+ doping suppresses the Jahn-Teller effect by modulating the valence state of TM ions, thereby enhancing structural stability; effectively strengthens the bond energy between TM―TM and between TM―O, reduces the spacing between TM layers and minimizes the possibility of TM ion migration; reduces the particle size of cathode materials, shortens the transmission distance of Na+ and enhances diffusion capability. The modified NaFe0.5Mn0.5-xInxO2 exhibits improved rate performance and cycling stability within the 2.0-4.0 V voltage, offering a reversible capacity of 111.4 mA·h/g. After 200 cycles, its capacity retention rate increases from 25.78% to 93.62%. |
| HTML 查看全文 查看/发表评论 下载PDF阅读器 |
