Ma Wei-Wei, Yu Hai-Tao, Guo Chen-Feng, Xie Ying, Ren Ning, Yi Ting-Feng
Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials Science, Heilongjiang University Harbin 150080 PR China
Zhejiang Chilwee Chuangyuan Industry Co., Ltd Changxing Zhejiang 313100 PR China
RSC Adv. 2019 May 21;9(28):15763-15771. doi: 10.1039/c9ra02392e. eCollection 2019 May 20.
To improve their electrochemical performance and structural stability, NaLiTiO (NLTO) nanoparticles were synthesized and then coated with a very thin MgF layer. Microscopy confirmed that the MgF-NLTO particles are about 150-250 nm in size, and that the thickness of the MgF layer for the MgF-NLTO-5 sample is ∼5 nm. Electrochemical measurements showed that the charge-discharge specific capacities of the five samples under a current density of 50 mA g after 100 cycles are 110.4/110.7, 150.7/151.3, 181.1/182.1, 205.7/206.9 and 238.9/239.2 mA h g, showing that the performance of MgF-NLTO-5 is the best among all the samples. Thanks to the thin coating layer, the polarization of the anode was reduced significantly, and its reversibility and lithium diffusion dynamics were also improved obviously. The performance improvement can be attributed to the suppression of surface corrosion and the enhancement of structural stability.
为了提高其电化学性能和结构稳定性,合成了纳米级的NaLiTiO(NLTO),然后在其表面包覆了一层极薄的MgF层。显微镜检查证实,MgF-NLTO颗粒的尺寸约为150-250nm,MgF-NLTO-5样品的MgF层厚度约为5nm。电化学测量表明,五个样品在50mA g电流密度下循环100次后的充放电比容量分别为110.4/110.7、150.7/151.3、181.1/182.1、205.7/206.9和238.9/239.2 mA h g,表明MgF-NLTO-5的性能在所有样品中最佳。由于有薄涂层,阳极的极化显著降低,其可逆性和锂扩散动力学也明显改善。性能的提高可归因于表面腐蚀的抑制和结构稳定性的增强。