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Abstract: Hydrogen adsorption studies of silver-embedded carbon nanotubes (Ag/CNTs) synthesized by in situ reduction method were performed at 298K and hydrogen equilibrium pressure of 23atm. The saturated reversible hydrogen storage capacity exhibited by silver embedded carbon nanotubes is found to be 0.86wt.% which is nearly 40% more as compared to the hydrogen uptake of purified carbon nanotubes measured under similar experimental conditions. The enhanced hydrogen storage capacity of carbon nanotubes is attributed to the spillover of physisorbed hydrogen from silver nanoparticles. The hydrogen uptake by Ag/CNT samples follows the Henry’s rule, suggesting that there is no significant adsorbate–adsorbate interaction in the low-pressure region. XRD spectrum indicated that 32% increase in particle size was observed in hydrogenated samples as compared to non-hydrogenated samples. [Copyright &y& Elsevier]

Abstract: A comparative study of the dehydrogenation of pure, ScCl3-, TiCl3-, VCl3-, and MnCl2-doped sodium alanate is reported. The samples wet-doped with transition metal halides exhibit significant lowering of both first and second dehydrogenation temperatures when compared with the pure sodium alanate. The reduction of the dehydrogenation temperature, ΔT dec, is maximum for the VCl3-doped alanates: 37 and 55°C, respectively, for the decomposition steps yielding Na3AlH6 and NaH. Among the transition metal halides, the order in which the decomposition temperature is lowered is Mn

Abstract: Hydrogen uptake of Pt–Pd alloy decorated MWCNTs was performed under ambient temperature and moderate pressures. Nanocrystalline alloy is coated on the MWCNTs via thermal vapour deposition (TVD) method. The size of the Pt–Pd alloy decorated by TVD on MWCNTs is 5nm. The maximum reversible hydrogen storage exhibited by nanocomposite, measured at 298K and pressure of 20atm is found to be ∼2.0wt.%, which is nearly 3 times more as compared to pristine CNTs performed under similar experimental conditions. The improvement of hydrogen storage in coated sample as compared to pristine CNTs is due to the spillover of physisorbed hydrogen from the alloy nanoparticles to the CNTs. [Copyright &y& Elsevier]