“…Embedding vacancies-dopants in the graphene structure is another strategy to improve the reactivity of graphene for hydrogen storage. Various doped graphene structures with vacancies have been examined [ 68 , 69 , 93 , 119 , 125 , 143 , 146 , 147 , 148 , 149 , 150 , 151 , 152 , 153 , 154 , 155 , 156 ]. For instance, graphene with SW defects and doped with Li was investigated using a PBE functional with dispersion corrections [ 68 ].…”