Hou Li, Cui Ruiwen, Xiong Shuangsheng, Jiang Xinyu, Wang Dong, Jiang Yang, Deng Shuolei, Guo Yuanyuan, Gao Faming
Hebei Key Laboratory of Applied Chemistry, School of Environmental and Chemical Engineering, Yanshan University, 438 West Hebei Street, Qinhuangdao 066004, China.
Phys Chem Chem Phys. 2021 Feb 19;23(6):3934-3941. doi: 10.1039/d0cp05434h.
Nowadays with the increasing demand for lithium-ion batteries (LIBs), the high-capacity silicon anode is becoming a promising electrode material. However, the huge expansion of silicon during long cycling remains a significant challenge. Herein, a functional double layer Si-based multi-component structure Si@void C@TiO2 was designed as anode material for lithium-ion batteries. This structure has a void space inside and a double shell composed of carbon layer and crystalline TiO2 outside, which not only takes effective in improving electric conductivity of the Si electrode material, but also maintains the structural stability and integrity of the electrode. The layers impede the electrolyte from contacting with Si, contributing to forming a stable SEI film and providing high Coulombic efficiency. Therefore, the Si@void C@TiO2 electrode provides a high reversible capacity of 1251 mA h g-1, and stable long cycling with a capacity of 668 mA h g-1 over 500 cycles at a current density of 100 mA g-1, and 98% average Coulombic efficiency, making this potential superior material Si-based multi-component anode a high-performance electrode material for Li-ion batteries.
如今，随着对锂离子电池（LIBs）需求的不断增加，高容量硅阳极正成为一种有前景的电极材料。然而，硅在长循环过程中的巨大膨胀仍然是一个重大挑战。在此，设计了一种功能性双层硅基多组分结构Si@void C@TiO2作为锂离子电池的阳极材料。这种结构内部有一个空隙空间，外部有由碳层和结晶TiO2组成的双层壳，这不仅有效地提高了硅电极材料的电导率，而且保持了电极的结构稳定性和完整性。这些层阻碍了电解质与硅接触，有助于形成稳定的固体电解质界面（SEI）膜并提供高库仑效率。因此，Si@void C@TiO2电极提供了1251 mA h g-¹的高可逆容量，并在100 mA g-¹的电流密度下，在500次循环中以668 mA h g-¹的容量稳定长循环，平均库仑效率为98%，使这种具有潜力的优质材料硅基多组分阳极成为锂离子电池的高性能电极材料。
