Abstract
Developing lightweight and reversible hydrogen storage media remains a major barrier to realizing practical hydrogen‐energy technologies. Here, first-principles density functional theory (DFT) calculations are employed to investigate how boron doping, lithium decoration, and single-carbon vacancies collectively govern the adsorption and desorption of molecular hydrogen on graphene. Twelve structural configurations were systematically examined to establish quantitative design relationships between dopant topology, Li anchoring strength, hydrogen coverage, and adsorption thermodynamics. The introduction of single-carbon vacancies markedly strengthens Li–graphene interactions, suppresses Li aggregation, and enhances hydrogen uptake through charge redistribution. Among the examined systems, 2BGrLiSCV and 3BGrLiSCV-2 exhibit optimal behavior, combining moderate adsorption energies (−0.32 to −0.35 eV per H 2 ) with a smooth and monotonic weakening of adsorption strength as hydrogen coverage increases, enabling reversible storage of up to seven and five H 2 molecules, respectively. These systems maintain moderate desorption temperatures under both atmospheric and elevated pressures. Projected-density-of-states and charge-density analyses reveal that boron-induced electron deficiency stabilizes Li + adsorption centers and binds H 2 via electrostatic polarization, consistent with physisorption. These results provide atomistic design principles linking adsorption energetics, desorption controllability, and structural stability, and identify defect- and dopant-engineered graphene as a tunable platform for near-ambient, reversible hydrogen storage applications.