Remarkable Uptake of CO 2 and CH 4 by Graphene‐Like Borocarbonitrides, B x C y N z

The surface areas and uptake of CO 2 and CH 4 by four graphene samples are measured and compared with activated charcoal. The surface areas are in the range of 5–640 m 2  g −1 , whereas the CO 2 and CH 4 uptake values are in the range of 18–45 wt % (at 195 K, 0.1 MPa) and 0–2.8 wt % (at 273 K, 5 MPa), respectively. The CO 2 and CH 4 uptake values of the graphene samples vary linearly with the surface area. In contrast, graphene‐like B x C y N z samples with compositions close to BC 2 N exhibit surface areas in the range of 1500–1990 m 2  g −1 and CO 2 and CH 4 uptake values in the ranges 97–128 wt % (at 195 K, 0.1 MPa) and 7.5–17.3 wt %, respectively. The uptake of these gases varies exponentially with the surface area of the B x C y Z n samples, and the uptake of CH 4 varies proportionally with that of CO 2 . The uptake of CO 2 for the best BC 2 N sample is 64 wt % at 298 K. The large uptake of both CO 2 and CH 4 gases by BC 2 N betters the performance of graphenes and activated charcoal. First‐principles calculations show that the adsorption of CO 2 and CH 4 is more favored on BCN samples compared to graphene.