CO2 capture and separation on the penta-BN2 monolayer with the assistance of charge/electric field

The efficient CO2 capture, separation, storage and utilization have received increasing attention to alleviate carbon emission and greenhouse effect. In this work, the first-principles calculations were performed to investigate the adsorption behaviors of CO2, H2, N2 and CH4 on the penta-BN2 monolayer with different charge density/electric field intensity, which aims to explore the possibility of penta-BN2 sheet as an alternative CO2 capture material. The results show that the CO2 is physisorbed on the neutral penta-BN2 sheet, whereas the interactions between the CO2 and the penta-BN2 surface would be significantly strengthened after introducing appropriate negative charge density/electric field. Interestingly, the CO2 adsorption/desorption processes are spontaneous, reversible and could be effortlessly controlled by introducing/removing extra electrons or external electric field into/from the penta-BN2 nanosheet. The adsorption strength of H2, N2 and CH4 is weaker than that of CO2 on penta-BN2 sheet under the condition of charge/electric field. Namely, the CO2 could be effectively captured and separated from the mixtures of H2, N2 and CH4 with the assistance of negative charge/electric field. These theoretical conclusions could provide a helpful guideline in search of materials with excellent CO2 capture capacity.