Abstract
Dissociative adsorption of hydrogen on catalyst sites followed by surface diffusion (spillover) to a carbon support was first reported for Pt-carbon catalysts (Robell, 1964) and was soon accepted as a valid step of numerous catalytic reactions. However, the concept of metal-assisted hydrogen storage (Schwarz, 1988) based on spillover entered much later the hydrogen community (Lueking and Yang, 2002) and is gaining recognition slowly as an alternate approach for enhancing hydrogen storage capacity of microporous materials for fuel-cell powered vehicles. This talk will analyze the significance and limits of the spillover mechanism for adsorptive storage of hydrogen, with examples of enhanced hydrogen uptake on Pd-containing activated carbon fibers. Evidence of the atomic nature of spilt-over hydrogen will be presented based on experimental results from inelastic neutron spectroscopy studies. Research sponsored by the Division of Materials Sciences and Engineering, U.S. Department of Energy under contract with UT-Battelle, LLC.
