Electric field assisted activation of CO₂ over P-doped graphene: A DFT study

The aim of the present study is to investigate the possibility of using phosphorous-doped graphene (P-Gr) as an efficient and selective sorbent for capture and storage of CO₂. Density functional theory calculations indicate that in the absence of the electric field, CO₂ weakly interacts with the P atom of P-Gr. However, when an electric field of 0.013-0.020 au is applied, CO₂ is strongly chemisorbed over P-Gr. Meanwhile, the chemisorbed CO₂ can be easily released from the P-Gr surface as the electric field is removed. This indicates that the storage and release of CO₂ may be controlled by applying an electric field in the range of 0.013-0.020 au. According to our results, P-Gr can selectively capture CO₂ from a CO₂/N₂ mixture under the electric field due to the difference between the adsorption energies of CO₂ and N₂.