Penta-graphene as a promising controllable CO2 capture and separation material in an electric field

Abstract

Controllable, highly selective, and reversible capture of CO2 by applying an electric field is an effective strategy to reduce greenhouse effect. This study, for the first time, introduced the application of penta-graphene (PG) nanosheet in an electric field as an ideal adsorbent material for CO2 adsorption and separation over H2 and CH4 by using density functional theory. Results showed that the binding strength of CO2 on PG nanosheet could be remarkably enhanced by applying an electric field. The adsorbed CO2 underwent a transition from physisorption to chemisorption in an electric field by increasing from 0.025 to 0.030 a.u.. Moreover, CO2 adsorption/desorption on PG nanosheet could be readily controlled by switching on/off an applied electric field of 0.030–0.040 a.u.. The interactions between H2/CH4 and PG nanosheet were relatively weak and increased slightly as the electric field increased, indicating that CO2 could be effectively separated from their mixtures in continuously variable electric field. This study highlighted the potential of PG nanosheet as a high-performance, controllable CO2 capture, regeneration, and separation material in an electric field.