The effects of bromine treatment on the hydrogen storage properties of multi-walled carbon nanotubes

The effects of bromine treatment on the properties of multi-walled carbon nanotubes (MWCNTs) such as surface porosity, sp2 hybridization, functional groups and hydrogen storage capacity were studied and compared with treated MWCNTs by HCl, HNO3 and H2SO4 acids. The treatments affect the graphitization properties (sp2 hybridization) and porous structures of MWCNTs by enlarging the specific surface area and the micro-pore volume. In addition, the hydrogen storage capacity of the treated MWCNTs was also investigated by volumetric technique. It is found that the destroying of sp2 hybridization of bromine treated MWCNTs increases hydrogen adsorption sites and decreases hydrogen desorption temperature.