Hydrogen storage in graphitic carbon nitride coordinated with boron clusters: A DFT study

The search for novel materials capable of adsorbing molecular hydrogen is of great interest due to the urgent need to replace polluting fossil fuels with clean energy sources. This study evaluates the adsorption of hydrogen molecules using computational methods, specifically density functional theory (M06-2X) combined with the def2-TZVP basis set, in complexes formed with graphitic carbon nitride, gC3N4, and boron clusters (Bn, n = 1-6). The average adsorption energy values for the B-H2 interactions range from -0.11 to -0.08 eV. To assess the spontaneity of these adsorption processes, Gibbs free energies were calculated for the temperatures 50-400 K. The results indicate that gC3N4Bn complexes can adsorb from 2 to 7 hydrogen molecules. Calculations confirm that adsorption remains spontaneous across the temperature range studied, which makes the gC3N4Bn complexes promising for hydrogen storage applications.