Kong Qingquan, Feng Wei, Wang Qingyuan, Gan Li-Yong, Sun Chenghua
School of Mechanical Engineering, Chengdu University, Chengdu, 610106, Sichuan, China.
Superconductivity and New Energy R&D Center, Southwest Jiaotong University, Chengdu, 610031 Sichuan, China.
Phys Chem Chem Phys. 2017 Mar 22;19(12):8563-8567. doi: 10.1039/c7cp00379j.
Recently, a two-dimensional Pma2-SiS monolayer has been predicted to show promising electronic properties [Nano Lett., 2015, 16, 1110]. However, it is suggested that Pma2-SiS is not suitable as an anode for Li-ion batteries [J. Power Sources, 2016, 331, 391]. By employing density functional theory calculations, we find that an ultrahigh theoretical specific capacity of 893.4 mA h g can be achieved in Pma2-SiS due to the strong bonding between Li and the S atoms released from Si-S bond breakage. Additionally, the low barrier of Li-diffusion (0.08 eV) along the Si-Si bond direction and the moderate average voltage (1.12 V) of the Li intercalation suggest that Pma2-SiS is promising as an anode material for Li-ion battery applications.
最近,二维Pma2-SiS单层被预测具有良好的电子特性[《纳米快报》,2015年,16卷,第1110页]。然而,有人认为Pma2-SiS不适合用作锂离子电池的阳极[《电源杂志》,2016年,331卷,第391页]。通过采用密度泛函理论计算,我们发现由于锂与从Si-S键断裂释放的S原子之间的强键合,Pma2-SiS可实现893.4 mA h g的超高理论比容量。此外,锂沿Si-Si键方向扩散的低势垒(0.08 eV)以及锂嵌入的适度平均电压(1.12 V)表明,Pma2-SiS作为锂离子电池应用的阳极材料具有潜力。