Yan Ji, Chang Xin-Bo, Ma Xiao-Kai, Wang Heng, Zhang Yong, Gao Ke-Zheng, Yoshikawa Hirofumi, Wang Li-Zhen
School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou 450001, China.
School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan.
Materials (Basel). 2020 Dec 23;14(1):24. doi: 10.3390/ma14010024.
Phosphorization of metal oxides/hydoxides to promote electronic conductivity as a promising strategy has attracted enormous attention for improving the electrochemical properties of anode material in lithium ion batteries. For this article, selective phosphorization from NiCoO to NiO/NiCoP microspheres was realized as an efficient route to enhance the electrochemical lithium storage properties of bimetal Ni-Co based anode materials. The results show that varying phosphorizaed reagent amount can significantly affect the transformation of crystalline structure from NiCoO to intermediate NiO, hybrid NiO/NiCoP, and, finally, to NiCoP, during which alterated sphere morphology, shifted surface valance, and enhanced lithium-ion storage behavior are detected. The optimized phosphorization with 1:3 reagent mass ratio can maintain the spherical architecture, hold hybrid crystal structure, and improve the reversibly electrochemical lithium-ion storage properties. A specific capacity of 415 mAh g is achieved at 100 mA g specific current and maintains at 106 mAh g when the specific current increases to 5000 mA g. Even after 200 cycles at 500 mA g, the optimized electrode still delivers 224 mAh g of specific capacity, exhibiting desirable cycling stability. We believe that understanding of such selective phosphorization can further evoke a particular research enthusiasm for anode materials in lithium ion battery with high performances.
金属氧化物/氢氧化物的磷化处理以促进电子传导作为一种有前景的策略，在改善锂离子电池负极材料的电化学性能方面已引起了广泛关注。在本文中，实现了从NiCoO到NiO/NiCoP微球的选择性磷化处理，这是增强双金属Ni-Co基负极材料电化学储锂性能的有效途径。结果表明，改变磷化试剂的用量会显著影响晶体结构从NiCoO到中间产物NiO、混合相NiO/NiCoP，最终到NiCoP的转变，在此过程中，检测到球形形态的改变、表面价态的变化以及锂离子存储行为的增强。试剂质量比为1:3的优化磷化处理能够保持球形结构，维持混合晶体结构，并改善可逆的电化学锂离子存储性能。在100 mA g的特定电流下实现了415 mAh g的比容量，当特定电流增加到5000 mA g时，比容量保持在106 mAh g。即使在500 mA g下循环200次后，优化后的电极仍能提供224 mAh g的比容量，展现出良好的循环稳定性。我们相信，对这种选择性磷化处理的理解能够进一步激发对高性能锂离子电池负极材料的特定研究热情。
