Reversible CO2 adsorption by an activated nitrogen doped graphene/polyaniline material

Abstract

For effective adsorption of carbon dioxide (CO2), we investigate a porous N functionalized graphene adsorbent produced by the chemical activation of a reduced graphene oxide/polyaniline composite. The N-doped graphene composite is microporous with a maximum BET surface area of 1336 m(2) g(-1). It shows a highly reversible maximum CO2 storage capacity of 2.7 mmol g(-1) at 298 K and 1 atm (5.8 mmol g(-1) at 273 K and 1 atm). The N-doped graphene shows good stability during recycling with only an initial decrease of 10% (3-2 .7 mmol g(-1)) in adsorption capacity before attaining a cycling equilibrium. The adsorbance capacity is correlated with N content x pore volume or N content x surface area. Given that there is no proper correlation parameter, these factors can be used to increase the CO2 adsorption capacity of N-doped graphene materials for practical utility. The as synthesized material also displays selectivity towards CO2 adsorption compared to H-2, N-2, Ar or CH4. The as formed material shows that graphene can be uniformly N-doped using the presented synthetic method.