Effect of exfoliation temperature on carbon dioxide capture of graphene nanoplates

Thermally exfoliated graphene nanoplates were found to be a novel high efficiency sorbent for the capture of CO(2). The exfoliated graphene nanoplates were expanded successfully from graphite oxide by a low-heat treatment at temperatures ranging from 150 to 400°C under vacuum conditions. The texture was analyzed by N(2) full isotherms and XRD. The CO(2) capture characteristics of the graphene nanoplates at 25°C and 30 bar were examined using a pressure-composition-temperature apparatus. The inter-layer spacing of the graphene layers and pore structure on the CO(2) capture capacities were studied as a function of the processing conditions. The prepared graphene nanoplates exhibited high capture capacities, up to 248 wt.%, at 25°C and 30 bar. The improved CO(2) capture capacity of the graphene nanoplates was attributed to the larger inter-layer spacing and higher interior void volume.