Investigations of hydrogen storage in palladium decorated graphene nanoplatelets

Carbon based nanomaterials are ideal media for hydrogen storage due to their highly porous structure, low density, and large surface area. The hydrogen uptake capacity of different carbon nanomaterials can be enhanced by spill over mechanism from a supported transition metal catalyst. In the present work graphene nanoplatelets (GNP) were prepared by thermal exfoliation method and decorated with palladium nanoparticles (Pd/GNP) by ethylene glycol reduction method. The high pressure hydrogen adsorption/desorption measurements were carried out for GNP and Pd/GNP using Sieverts apparatus in the temperature and pressure ranges of 25-100°C and 0.1-4 MPa, respectively. The hydrogen storage capacity of GNP and Pd/GNP were found to be 0.28 wt% and 1.21 wt% respectively at 25°C and 3.2 MPa pressure. Uniform dispersion of palladium nanoparticles over the surface of GNP enhances the hydrogen storage capacity of GNP by 70% due to spill over mechanism. © 2011 Indian Institute of Metals.