LAUSR

Hydrogen dissociation is a key step in almost all hydrogenation reactions; therefore, an efficient and cost-effective catalyst with a favorable band structure for this step is highly desirable. In the current work, transition metal-based C20 (M@C20) complexes are designed and evaluated as single-atom catalysts (SACs) for hydrogen dissociation reaction (HDR). Interaction energy (Eint) analysis reveals that all the M@C20 complexes are thermodynamically stable, whereas the highest stability is observed for the Ni@C20 complex (Eint = −6.14 eV). Moreover, the best catalytic performance for H2 dissociation reaction is computed for the Zn@C20 catalyst (Eads = 0.53 eV) followed by Ti@C20 (Eads = 0.65 eV) and Sc@C20 (Eads = 0.76 eV) among all considered catalysts. QTAIM analyses reveal covalent or shared shell interactions in H2* + M@C20 systems, which promote the process of H2 dissociation over M@C20 complexes. NBO and EDD analyses declare that transfer of charge from the metal atom to the antibonding orbital of H2 causes dissociation of the H–H bond. Overall outcomes of this study reveal that the Zn@C20 catalyst can act as a highly efficient, low-cost, abundant, and precious metal-free SAC to effectively catalyze HDR.