In this work graphite nanofibers (GNFs) were successfully expanded intercalating KOH followed by heat treatment in the temperature range of 700-1000 degrees C The aim was to improve the CO2 adsorption capacity of the GNFs by increasing the porosity of GNFs The effects of heat treatment on the pore structures of GNFs were investigated by N-2 full isotherms XRD SEM and TEM The CO2 adsorption capacity was measured by CO2 isothermal adsorption at 25 degrees C and 1 atm From the results it was found that the activation temperature had a major influence on CO2 adsorption capacity and textural properties of GNFs The specific surface area total pore volume and mesopore volume of the GNFs increased after heat treatment The CO2 adsorption isotherms showed that G-900 exhibited the best CO2 adsorption capacity with 59 2 mg/g (C) 2010 Elsevier Inc All rights reserved