Hydrogen storage in a Ni-B nanoalloy-doped three-dimensional graphene material

A three-dimensional graphene material was doped with Ni-B nanoalloys via a chemical reduction process. The graphene doped with Ni (0.83 wt%) and B (1.09 wt%) shows the best hydrogen storage capacity of 4.4 wt% at 77 K and 106 kPa, which is better than that of pristine graphene by three times, and is also excellent among all carbon-based materials. Analysis of hydrogen isotherms and isosteric heat of adsorption suggests that doping with an appropriate amount of Ni-B nanoalloys can result in the dissociative chemisorption of hydrogen molecules by spillover to achieve the high hydrogen storage capacity.