Hydrogen uptake of high-energy ball milled nickel-multiwalled carbon nanotube composites

Hydrogen uptake of Ni decorated MWCNT composites performed using Serverʹs volumetric equipment. The maximum reversible hydrogen storage capacity exhibited by nanocomposites, measured at 298 K and hydrogen pressure of 8 MPa, was found to be ∼2.27 wt.%, which is more than three times as compared to pristine MWCNTs. The enhancement of hydrogen storage capacity in coated samples as compared to pristine MWCNTs is due to the spillover of physisorbed hydrogen from metal nanoparticles to the MWCNTs. The hydrogen uptake by Ni/MWCNTs samples follows the Henryʹs rule, suggesting that there is no significant adsorbate–adsorbate interaction in the low-pressure region.