Nb3SiT6 (T = S, Se, and Te) monolayers with the highly efficient catalytic performance for lithium–sulfur batteries: Insights from a first-principles study

Abstract

The first-principles calculations were performed to investigate the performance of Li–S batteries on a series of two-dimensional (2D) monolayers, Nb3SiT6 (T = S, Se, and Te), Nb3GeTe6, and Ta3SiTe6. These monolayers show high kinetics of thermal stability and are accessible in the experiment. The S8/Li2Sn species can be efficiently anchored by these monolayers. The high-degree electron redistribution between Li2Sn and substrates is responsible for the moderate adsorption ability. The metallic behaviors of all monolayers studied are well maintained upon the adsorption of S8/Li2Sn. Notably, the high bifunctional catalytic activity of these monolayers is found in both the sulfur reduction reaction and the Li2S decomposition reaction. The Nb3SiT6 (T = S, Se, and Te), Nb3GeTe6, and Ta3SiTe6 monolayers with highly efficient catalytic performance could be promising anchoring materials in Li–S batteries.