Lin Liyang, Li Mengjun, Yan Ying, Tian Yuanhao, Qing Juan, Chen Susu
School of Aeronautics, Chongqing Jiaotong University, Chongqing 400074, China.
Chongqing Key Laboratory of Green Aviation Energy and Power, Chongqing Jiaotong University, Chongqing 400074, China.
Dalton Trans. 2024 Oct 22;53(41):16871-16878. doi: 10.1039/d4dt02623c.
The volume expansion and poor conductivity greatly limit the application of silicon as an anode for lithium-ion batteries. Although nanocrystallization of silicon and its surface carbon coating can be improved to some extent, the serious problems of particle aggregation and structural instability have not been effectively solved. In this paper, gelatin and sodium alginate (GE + SA) derived carbon/silicon composites are successfully prepared by a liquid-phase method, the freeze-drying technique, and heat treatment. Si nanoparticles (NPs) are uniformly encapsulated in a three-dimensional network of N-doped carbon that is enriched with a rich pore structure. The reversible capacity of the particular Si@C composite electrode was maintained at 580 mA h g after 300 cycles at a current density of 1 A g, showing good cycling stability. Meanwhile, the anode also has excellent rate performance with reversible capacities of 2230, 1458, 1101, and 686.6 mA h g at current densities of 0.1, 0.5, 1, and 2 A g, respectively. The GE + SA derived carbon/silicon composites effectively solve the problems of particle aggregation and an unstable carbon/silicon interface structure and can become candidates for anode materials in lithium-ion batteries.
体积膨胀和导电性差极大地限制了硅作为锂离子电池负极的应用。尽管硅的纳米晶化及其表面碳涂层可在一定程度上得到改善，但颗粒团聚和结构不稳定等严重问题尚未得到有效解决。本文通过液相法、冷冻干燥技术和热处理成功制备了明胶和海藻酸钠（GE + SA）衍生的碳/硅复合材料。硅纳米颗粒（NPs）均匀地包裹在富含丰富孔隙结构的氮掺杂碳的三维网络中。在1 A g的电流密度下循环300次后，特定的Si@C复合电极的可逆容量保持在580 mA h g，显示出良好的循环稳定性。同时，该负极在0.1、0.5、1和2 A g的电流密度下分别具有2230、1458、1101和686.6 mA h g的可逆容量，具有优异的倍率性能。GE + SA衍生的碳/硅复合材料有效解决了颗粒团聚和碳/硅界面结构不稳定的问题，有望成为锂离子电池负极材料的候选者。
