Hydrogen storage in heat-treated carbon nanofibers prepared by the vertical floating catalyst method

Hydrogen storage in carbon nanofibers (CNFs) prepared by the floating catalyst method is investigated. The pristine CNF materials are subjected to several heat treatments under different temperatures with the protection of Ar for 2 h to get favorable structure and adsorption surface. These treatments improved the graphitization degree and surface activity of the CNFs effectively. At last these materials can absorb ∼4 wt.% of hydrogen at room temperature under ∼10 MPa. The effect of the surface functional groups on the adsorption performance of the CNFs is highlighted.