Revisiting Hydrogen Storage in Bulk BC3

Using density functional theory, we investigated the hydrogen storage properties of bulk BC3. The minimum energy pathway to move H, molecules front the gas phase into the lattice through the edges of the layered, crystalline material was determined. In contrast to the large energy barriers for H-2 diffusion into crystalline graphite, we found H-2 migration into bulk BC3 is both thermodynamically and kinetically feasible. Within the BC3 lattice, H-2 will undergo dissociative chemisorption to form C-H bonds, which provides a chemical driving force for H-2 intercalation. The calculated H-2 chemisorption energies in bulk BC3 based on the generalized gradient approximation suggest that the adsorption strength is modest, making the material a promising candidate for reversible hydrogen storage under near-ambient conditions.