Li Jianbin, Liu Wenjing, Qiao Yingjun, Peng Gongchang, Ren Yurong, Xie Zhengwei, Qu Meizhen
Department of Nano Carbon Materials, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu, China.
Group of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing, China.
Front Chem. 2020 Sep 11;8:666. doi: 10.3389/fchem.2020.00666. eCollection 2020.
Silicon anodes with an extremely high theoretical specific capacity of 4,200 mAh g have been considered as one of the most promising anode materials for next-generation lithium-ion batteries. However, the large volume expansion during lithiation hinders its practical application. In this work, pomegranate-like Si@SiO composites were prepared using a simple spray drying process, during which silicon nanoparticles reacted with oxygen and generated SiO on the surface. The thickness of the SiO layer was tuned by adjusting the drying temperature. In the unique architecture, the SiO which serves as the protection layer and the void space in pomegranate-like structure could alleviate the volume expansion during repeated lithium insertion/extraction. As a lithium-ion battery anode, pomegranate-like Si@SiO composites dried at 180°C delivered a high specific capacity of 1746.5 mAh g after 300 cycles at 500 mA g.
具有4200 mAh g极高理论比容量的硅阳极被认为是下一代锂离子电池最有前途的阳极材料之一。然而，锂化过程中的大量体积膨胀阻碍了其实际应用。在这项工作中，采用简单的喷雾干燥工艺制备了石榴状Si@SiO复合材料，在此过程中硅纳米颗粒与氧气反应并在表面生成SiO。通过调节干燥温度来调整SiO层的厚度。在这种独特的结构中，作为保护层的SiO和石榴状结构中的空隙空间可以减轻反复锂嵌入/脱出过程中的体积膨胀。作为锂离子电池阳极，在180°C下干燥的石榴状Si@SiO复合材料在500 mA g下循环300次后具有1746.5 mAh g的高比容量。
