Strong chemical adsorption of CO2 and N2 on a five-vacancy graphene surface

Carbon dioxide adsorption on a five-vacancy graphene surface was mainly studied using density functional theory. Molecular nitrogen was also studied in order to analyze the selectivity for CO2 of this surface with respect to N-2. Strong chemical adsorption energies were observed for CO2 (-6.09 eV) and N-2 (-4.34 eV). A planar heterocyclic system together with a metal-semimetal (an apparent gap of 0.17 eV) electronic transition was obtained after CO2 adsorption. No electronic transition was observed after N-2 adsorption. Electronic charge transfer from the five-vacancy graphene surface to CO2 and N-2 is consequence of the leftward shift of the Fermi energy of the five-vacancy graphene surface with respect to the Dirac point indicating p-doping charge transfer mechanism. On the other hand, a decrease in the magnetic moment was observed as a consequence of the adsorption of both molecules. The former findings could be used to create surfaces with strong and more sensitive CO2 adsorption and CO2 electronic sensors.

Automated summary

In this study, the adsorption of CO2 on a five-vacancy graphene surface was investigated using density functional theory. The selectivity of this surface for CO2 compared to N-2 was also analyzed. The results showed strong chemical adsorption for both CO2 and N-2, with distinct electronic structures and charge transfer mechanisms observed after CO2 adsorption.