Meng Tao, Li Bo, Wang Qiushi, Hao Junnan, Huang Binbin, Gu Feng Long, Xu Huimin, Liu Peng, Tong Yexiang
MOE of the Key Laboratory of Bioinorganic and Synthetic Chemistry, The Key Lab of Low-Carbon Chemistry & Energy Conservation of Guangdong Province, School of Chemistry, Sun Yat-sen University, Guangzhou 510275, People's Republic of China.
Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, School of Chemistry, South China Normal University, Guangzhou 510006, People's Republic of China.
ACS Nano. 2020 Jun 23;14(6):7066-7076. doi: 10.1021/acsnano.0c01796. Epub 2020 May 18.
The stereospecific design of the interface effects can optimize the electron/Li-ion migration kinetics for energy-storage materials. In this study, an electric field was introduced to silicon-based materials (C-SiO@Si/rGO) through the rational construction of multi-heterostructures. This was achieved by manipulating the physicochemical properties at the atomic level of advanced Li-ion batteries (LIBs). The experimental and density functional theory calculations showed that the unbalanced charge distribution generated a large potential difference, which in turn induced a large-scale electric-field response with a boosted interfacial charge transfer in the composite. The as-prepared C-SiO@Si/rGO anode showed advanced rate capability (.., 1579.0 and 906.5 mAh g at 1000 and 8000 mA g, respectively) when the migration paths of the Li-ion/electrons hierarchically optimized the large electric field. Furthermore, the C-SiO@Si/rGO composite with a high SiO@Si mass ratio (73.5 wt %) demonstrated a significantly enhanced structural stability with a 40% volume expansion. Additionally, when coupled with the LiNiCoMnO (NCM) cathode, the NCM//C-SiO@Si/rGO full cell delivers superior Li-ion storage properties with high reversible capacities of 157.6 and 101.4 mAh g at 500 and 4000 mA g, respectively. Therefore, the electric-field introduction using optimized electrochemical reaction kinetics can assist in the construction of other high-performance LIB materials.
界面效应的立体定向设计可以优化储能材料的电子/锂离子迁移动力学。在本研究中，通过合理构建多异质结构，将电场引入到硅基材料（C-SiO@Si/rGO）中。这是通过在先进锂离子电池（LIBs）的原子水平上操纵物理化学性质来实现的。实验和密度泛函理论计算表明，电荷分布不平衡产生了较大的电位差，进而在复合材料中诱导了大规模的电场响应，并促进了界面电荷转移。当锂离子/电子的迁移路径对大电场进行分层优化时，所制备的C-SiO@Si/rGO阳极表现出先进的倍率性能（分别在1000和8000 mA g下为1579.0和906.5 mAh g）。此外，具有高SiO@Si质量比（73.5 wt%）的C-SiO@Si/rGO复合材料在体积膨胀40%的情况下，结构稳定性显著增强。此外，当与LiNiCoMnO（NCM）阴极耦合时，NCM//C-SiO@Si/rGO全电池在500和4000 mA g下分别具有157.6和101.4 mAh g的高可逆容量，表现出优异的锂离子存储性能。因此，利用优化的电化学反应动力学引入电场有助于构建其他高性能的LIB材料。
