Hydrogen Adsorption on Manganese-Doped Carbon, Boron Nitride, and Silicon Carbide Nanocones: A Density Functional Theory Study

Abstract

The quest for efficient hydrogen storage media persists as a pivotal bottleneck in the transition toward large-scale hydrogen-based energy infrastructures. In the present study, systematic density functional theory (DFT) calculations were executed via the Gaussian 09 software package to scrutinize the hydrogen adsorption phenomena on pristine and manganese-doped nanocones (NCs) comprising
carbon (C), boron nitride (BN), and silicon carbide (SiC). By employing a rigorous computational framework, we evaluated the structural stability and electronic modulation of these nanostructures to determine their viability for storage applications. Our findings underscore the superiority of the Mn– Si41C34H9–M2 configuration characterized by a 300° disclination angle which demonstrated an
exceptionally robust interaction with molecular hydrogen. This specific system yielded a significant adsorption energy of -4.98 eV, accompanied by a pronounced dipole moment enhancement of 25.74 D, thereby indicating substantial surface polarization. Furthermore, the electronic landscape analysis revealed an ultra-narrow energy gap of 0.02 eV for the Mn-doped SiC nanocone, suggesting a highly reactive state that facilitates charge transfer processes. Natural Population Analysis (NPA) and molecular orbital insights indicate that Mn incorporation induces a localized electronic redistribution, creating potent catalytic sites for hydrogen binding. Comparative assessment confirms that Mn-doped SiC nanocones outperform their C and BN counterparts in terms of binding affinity, highlighting the indispensable role of transition-metal doping in fine-tuning the chemisorption characteristics. These results provide critical theoretical benchmarks for designing dopant-induced nanoscale platforms tailored for high-capacity hydrogen storage.