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 30bar 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 248wt.%, at 25°C and 30bar. The improved CO ₂ capture capacity of the graphene nanoplates was attributed to the larger inter-layer spacing and higher interior void volume.