Hydrogen Storage and Adsorption

Thomas, K.M., Hydrogen adsorption and storage on porous materials. Catal. Today 120,389-398, 2007. 

Spiral shaped hollow nanofibers were formed from the reaction of p-aminophenyl-p-D-glucopyranoside and p-dodecanoylaminophenyl-p-o-glucopyranoside with excess tetraethoxysilane. The diameter distributions of these tubes ranged from 1 to 2 nm and from 3 to 7 nm. Metal oxide nanotubes derived from this process displayed excellent hydrogen adsorption and storage capacity for potential use in hydrogen-powered vehicles. 

The synthesis of MOFs with optimum pore size and shape, and surface chemistry for hydrogen adsorption are possible using rational design strategies. The current status of studies of hydrogen adsorption and storage on porous MOFs is reviewed and future prospects are discussed. 

Hou et al. [73] considered small "carbon islands" as the main hydrogen-adsorption sites in an MWNT. The hydrogen-storage capacity of a CNT varies widely and the reason for such a variation is not clear, possibly caused by the impurity such as metal catalysts or amorphous carbon. It is not clear yet how the metallic catalyst particles, which are used during the preparation of nanotube samples, affect the hydrogen-storage capacity of nanotubes. 

For application purposes not only the excess adsorption, but also the compressed H2 in the void space of the material needs to be taken into account for calculating the total storage capacity. As an example, in Figure 6 the contribution of excess adsorption and compression on the total storage amount is visualised in a qualitative way for hydrogen stored at 298 K and 77 K. This example shows that for high temperatures and pressures the compression contribution gains importance, while at 77 K. the contribution of excess adsorption is more important. 

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