Han Junjie, Zhu Jianhui, He Xuanlong, Yang Ming, Yan Chenxi, Ma Dingtao, Zhang Lipeng, Zhang Peixin
College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, P. R. China.
School of Materials and New Energy, South China Normal University, Shanwei 516600, P. R. China.
ACS Appl Mater Interfaces. 2025 Jun 4;17(22):32381-32391. doi: 10.1021/acsami.5c03576. Epub 2025 May 23.
LiMnFePO is limited in practical applications due to its low electronic conductivity and slow Li diffusion rate. Therefore, Cu doping was applied to modify LiMnFePO, and the mechanism of Cu "three-function" synergistic enhancement of the cathode material performance was explored. Compared to the undoped sample (LMFP), the Cu-doped sample (LMFP-Cu 1%) exhibited significantly improved electronic conductivity and Li diffusion coefficient. First-principles calculations also confirmed the high electronic conductivity and low Li diffusion barrier of LiMnFePO@C. Additionally, LiMnFeCuPO@C demonstrated excellent rate performance and cycling stability, with discharge capacities of 160.3 mA h g and 121.2 mA h g at 0.1 and 2C rates, respectively. After 200 cycles at 1C rate, the capacity retention was 92.5%. The first principle calculation of DFT can help to show that the introduction of Cu can effectively reduce the diffusion barrier and intrinsic conductivity of Li, in situ XRD analysis revealed that LiMnFeCuPO@C exhibited good structural stability and reversibility. The incorporation of Cu represents a promising approach to improving the lithium storage capabilities of LiMnFePO cathode materials.
LiMnFePO由于其低电子电导率和缓慢的锂扩散速率而在实际应用中受到限制。因此，采用铜掺杂对LiMnFePO进行改性，并探索了铜“三功能”协同增强正极材料性能的机理。与未掺杂样品（LMFP）相比，铜掺杂样品（LMFP-Cu 1%）表现出显著提高的电子电导率和锂扩散系数。第一性原理计算也证实了LiMnFePO@C具有高电子电导率和低锂扩散势垒。此外，LiMnFeCuPO@C表现出优异的倍率性能和循环稳定性，在0.1C和2C倍率下的放电容量分别为160.3 mA h g和121.2 mA h g。在1C倍率下循环200次后，容量保持率为92.5%。DFT的第一性原理计算有助于表明铜的引入可以有效降低锂的扩散势垒和本征电导率，原位XRD分析表明LiMnFeCuPO@C表现出良好的结构稳定性和可逆性。铜的掺入是提高LiMnFePO正极材料锂存储能力的一种有前景的方法。
