Activation of functionalized graphene oxide incorporated poly acrylonitrile nanofibers for producing highly porous carbon nanostructures

Abstract

Porous carbon materials, including activated carbon nanofibers (ACNFs), have wide applications in the fields of recycling, separation, storage, drug delivery, etc. due to their high surface area and high porosity. On the other hand, the combination of these materials with graphene structures may have a synergistic effect on the properties of the product for the target application. In the present research, polyacrylonitrile nanofibers containing different percentages of synthesized graphene oxide, functionalized by chlorosulfonic acid were produced by the electrospinning method. Then, carbonization and activation were carried out to produce a porous activated carbon nanofibrous web. The investigation proved that the average diameter of the functionalized graphene oxide (FGO) incorporated PAN nanofibers increases as the amount of the incorporated FGO is increased. FESEM micrographs showed that the FGO incorporated nanofibers disfigure to some extent after activation, whereas the neat PAN nanofibers keep their original fiber form. XRD analysis showed that after activation, the D spacing in FGO-incorporated nanofibers decreases to some extent, but generally the effect of FGO on the microstructure of PAN nanofibers is not overwhelming. FTIR spectrum confirmed the presence of FGO in ACNFs. BET results showed that the specific surface area of the ACNF decreases with increasing amounts of the incorporated FGO. The maximum specific surface area recorded was 941.37 m2/g. This was lower than that of the neat ACNF (988.5 m2/g). Total pore volume showed the same trend. The presence of FGO in ACNFs leads to an increase in mesopores content and in other words, the share of micropores decreases.