Two-dimensional single-layer PC6 as promising anode materials for Li-ion batteries: The first-principles calculations study

•The binding energy of Li atoms adsorbed on SL PC6 are negative.•Li-ions tend to diffuse along path I in SL PC6 and the diffusion path is small.•The maximum theoretical specific capacity of SL PC6 as Li-ion batteries is 717.09 mAh/g.•The average OCV for single and double side adsorption is respectively 0.23 V and 0.21 V.