SnSe2 monolayer is a promising Na host material: A DFT study

Na ion batteries (SIBs) have attained tremendous consideration due to their environmental friendliness, natural abundance and low costs. In this study, the electronic and electrochemical characteristics of SnSe2 monolayer for SIBs are investigated by using first principle calculations. The electronic structure of 2D SnSe2 exhibit semiconducting character with band gap of 0.85 eV and 1.4 eV by using PBE-GGA and HSE06 schemes, respectively. Our computation revealed that Na adsorbed SnSe2 system demonstrate metallic characteristics. With rise of Na loading, the electronic conductivity of the host materials upsurges. An average open circuit voltage (OCV) of 0.662 V is perceived with Na storage capacity of 387 mAhg−1. This capacity is greater than the commercial anode materials (i.e. graphite has storage capacity of 372 mAhg−1 and 273 mAhg−1 for LIBs and KIBs, respectively). Furthermore, a significantly low activation energy (104 meV) for Na diffusion on the SnSe2 monolayer surface is obtained. Hence, these outcomes suggest that SnSe2 monolayer is a potential applicant for SIBs.