Effect of different reductants for palladium loading on hydrogen storage capacity of double-walled carbon nanotubes

The effects of different reductants for palladium loading on the hydrogen sorption characteristics of double-walled carbon nanotubes (DWCNTs) have been investigated. Pd nanoparticles were loaded on DWCNT surfaces for dissociation of H-2 into atomic hydrogen, which spills over to the defect sites on the DWCNTs. When we use different reductants, the reduction capabilities and other effects of the different reductants are different, which affects the hydrogen storage capacity of the DWCNTs. In this work, the amount of hydrogen storage capacity was determined (by AMC Gas Reactor Controller) to be 1.7, 2.0, 2.55, and 3.0 wt% for pristine DWCNTS and for 2.0%Pd/DWCNTs using H-2, L-ascorbic acid, and NaBH4 as reductants, respectively. We found that the hydrogen storage capacity can be enhanced by loading with 2% Pd nanoparticles and selecting a suitable reductant. Furthermore, the sorption can be attributed to the chemical reaction between atomic hydrogen and the dangling bonds of the DWCNTs. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.