Borophene Nanosheets-Grafted Covalent Organic Framework: A 2D Hybrid Porous Material for Hydrogen Adsorption Studies

Abstract Two-dimensional hybrid porous materials depicted potential in recent years for advancing gas adsorption strategies, particularly in the field of physisorbed H2 storage to meet future energy demands. Owing to their unique features, hybrid porous materials exhibit enhanced induction interactions with H2, enabling them to store higher gravimetric hydrogen capacities than their parent materials. In this study, we report a two-dimensional crystalline hybrid porous material, borophene-TpPa-1, synthesized by integrating borophene nanosheets into a covalent organic framework, TpPa-1. The hybrid remarkably exhibits enhanced hydrogen adsorption at 1.999 bar and 77 K, achieving a 1.6-fold higher uptake than TpPa-1. GCMC simulations attribute this observation to the enhanced enthalpy of adsorption (∼13 kJmol–1), reflecting the strengthened interactions between H2 and the hybrid. Furthermore, the DFT calculations identify favorable adsorption sites and confirm the formation of the hybrid structure. They also validate the enhanced H2 adsorption in terms of adsorption energies and charge redistribution. These results reveal that incorporating borophene into a porous material can significantly enhance hydrogen adsorption.