Figure 1

Alternative Hydrogen Storage Materials.
(a) Gravimetric and volumetric densities of various hydrogen storage materials and options. Inset shows the hydrogen storage density of alkanes as a function of the number of carbon atoms. (b) Dependence of the Gibbs free energy with temperature for the deep dehydrogenation reaction (or hydrogen formation reactions) of various straight-chain alkanes (i.e. CH4; n-C5H12, n-C10H22, n-C15H32 and n-C20H42). Inset shows the dependence of the standard enthalpy and entropy for the hydrogen formation reactions with carbon numbers of various lineal alkanes.