Hydrogen Storage Properties of Economical Graphene Materials Modified by Non-Precious Metal Nickel and Low-Content Palladium

Ni/Pd co-modified graphene hydrogen storage materials were successfully prepared by a solvothermal method using NiCl2 & BULL;6H(2)O and Pd(OAc)(2) and reduced graphene oxide (rGO). By adjusting the hydrothermal temperature, Pd-Ni is successfully alloyed, and the size of the obtained nanoparticles is uniform. The electronic structure of Pd was changed by alloying, and the center of the D-band moved down, which promoted the adsorption of hydrogen. The NiPd-rGO-180 sample, in which 180 represents the solvothermal temperature in centigrade (& DEG;C), has the highest hydrogen storage capacity of 2.65 wt% at a moderate condition (RT/4MPa). The excellent hydrogen storage performance benefits from the synergistic hydrogen spillover effect of Pd-Ni bimetal. The calculated hydrogen adsorption energies of Ni2Pd2-rGO are within the ideal range (-0.20 to -0.60 eV) of hydrogen ads/desorption; however, the introduction of substrate defects and the cluster orientation alter the hydrogen adsorption energy. This work provides an effective reference for the design and optimization of carbon-based hydrogen storage materials.