Influence of chemical functionalization on the CO2/N2 separation performance of porous graphene membranes

• Published in: Nanoscale 2012-09, Vol.4 (17), p.5477-5482
• Main Authors: Shan, Meixia, Xue, Qingzhong, Jing, Nuannuan, Ling, Cuicui, Zhang, Teng, Yan, Zifeng, Zheng, Jingtang
• Format: Article
• Language: English
• ISSN: 2040-3364; 2040-3372
• DOI: 10.1039/c2nr31402a

The separation of CO 2 from a mixture of CO 2 and N 2 using a porous graphene membrane was investigated using molecular dynamics (MD) simulations. The effects of chemical functionalization of the graphene sheet and pore rim on the gas separation performance of porous graphene membranes were examined. It was found that chemical functionalization of the graphene sheet can increase the absorption ability of CO 2 , while chemical functionalization of the pore rim can significantly improve the selectivity of CO 2 over N 2 . The results show that the porous graphene membrane with all-N modified pore-16 exhibits a higher CO 2 selectivity over N 2 (11) due to the enhanced electrostatic interactions compared to the unmodified graphene membrane. This demonstrates the potential use of functionalized porous graphene as single-atom-thick membrane for CO 2 and N 2 separation. We provide an effective way to improve the gas separation performance of porous graphene membranes, which may be useful for designing new concept membranes for other gases. The chemical functionalization of the pore rim with nitrogen atoms can significantly improve the gas separation performance of porous graphene membranes.