Hydrogen based fuel cells in automobiles may offerthe vital solution to the world’s socio-politicaldependence on oil. However a safe and efficient on-boardhydrogen storage system is necessary forcommercialization of fuel cell based automobiles. Storingof hydrogen in solid adsorbents is one of the options foron-board storage. According to the US Department ofEnergy an adsorbent should have hydrogen storagecapacity of 6.5 wt% for commercial applications. Severalresearchers have reported that carbon based adsorbents,particularly carbon nanotubes, carbon fibers, single wallnanotubes, are most promising for achieving the USDepartment of Energy’s targeted capacity for hydrogenstorage. A wide range of adsorption capacity for hydrogenreported on these adsorbents. However, Schimmel etal.[1] concluded that hydrogen storage capacity of carbonbased materials including carbon nanotubes, nanofibers,and single wall carbon nanotubes depended on the surfacearea of the individual materials and the maximum storagecapacity was found to be 2% only at low temperatures.The preliminary work by Ghosh, Prelas and their coworkerswith diamond plates and nanophase diamondpowder showed promise for storing hydrogen onnanophase diamond [2-4]. They also noted that thestorage capacity may be enhanced if the diamond surfaceis charged. The objective of this work was to treat thediamond surface with a fluorine compound. Fluorine canterminate the bonds on the diamond surface to attracthydrogen and keep it weakly bound to the surface.
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