Hydrogen Storage Properties of Complex Metal Hydride-Carbon Materials

摘要

Hydrogen storage properties of NaAlH4 can be improved by mixing it with Co/carbon catalysts. The importance of cobalt nanoparticles was established by varying the amount of active cobalt in the reaction vessel. This was achieved either by keeping the weight of NaAlH4 and carbon constant while varying the amount of Co/carbon catalyst used or by poisoning the cobalt active site with CO. Another approach to improve the hydrogen storage properties of complex metal hydride is through nano-con-finement of the hydride in carbon pores. LiBH4-carbon composite formed via liquid phase infusion of LiBH4 into carbon was examined for reversibility in the hydriding/ dehydriding cycles. The physical constraints imposed by the carbon nano-pores appeared to be effective in deterring the loss of cyclability due to sintering of the hydride. The loss in hydrogen storage appeared to be the result of LiBH4 reaction with impurities/reactive functional groups on the carbon.