SiS nanosheets as a promising anode material for Li-ion batteries: a computational study

Abstract

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⁻¹ 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.