Sustainable Gas Storage: CO₂ Activation of Edge-Functionalized Graphitic Nanoplatelets

Graphitic nanoplatelets (GnPs), edge-selectively carboxylated graphitic nanoplatelets (ECGnPs), are functionalized with a carboxylic acid at the edge increasing their surface area, and are highly dispersible in various solvents. However, there is a limit in that the basal plane remains intact because it is functionalized only in the part where the radical is generated at the edge. Here, we activate ECGnPs to have porous structures by flowing CO₂ at 900 °C. Etching of the ECGnPs structure was performed through the Boudouard reaction, and the surface area increased from 579 m² g^-1 to a maximum of 2462 m² g^-1. In addition, the pore structure was investigated with various adsorption gases (CH₄, Ar, CO₂, H₂, and N₂) according to the reaction time. This study provides the overall green chemistry in that it utilizes CO₂ from manufacturing to activation compared to the process of activating with conventional chemical treatment.