Using first principles approach, we investigate the catalytic activity of noble metal-free n-doped (C→B, O→N) hexagonal boron nitride (h-BN) monolayer for CO oxidation. To be mentioned CO adsorption ability, and hence the preferred Eiley-Rideal (ER) and Langmuir Hinshelwood (LH) mechanism for CO oxidation is dopant-dependent: CO is chemisorbed on O-doped h-BN (OBN) while it interacts physically with C-doped h-BN (CBN) surface. Even though both C and O doping create similar donor states below the Fermi level (E f ), the O doping results in larger bond length of O-B1 (one of the nearest B atom), out-of plane displacement of B1 atom and less positive charge on B1 atom, synergistically making this atom higher in activity. The presence of a pre-adsorbed O 2 molecule in both types of surfaces eliminates any chances of CO poisoning of the surface and CO oxidation prefers to proceed via ER mechanism with small activation barrier. The high values of Sabatier activities suggest doped h-BN surface to be superior to Au 55 and Pt 55 nanoclusters.In case of CO oxidation by means of LH mechanism, a stable O 2 ···CO intermediate is produced, which requires quite high barrier energy to break the O-O bond. However, the presence of a H 2 O molecule increases the activity of the catalyst and helps in catalytic CO de-

First-principles based calculations are performed to investigate the dehydrogenation kinetics considering doping at various layers of MgH2 (110) surface. Doping at first and second layer of MgH2 (110) has a significant role in lowering the H2 desorption (from surface) barrier energy, whereas the doping at third layer has no impact on the barrier energy. Molecular dynamics calculations are also performed to check the bonding strength, clusterization, and system stability. We study in details about the influence of doping on dehydrogenation, considering the screening factors such as formation enthalpy, bulk modulus, and gravimetric density. Screening based approach assist in finding Al and Sc as the best possible dopant in lowering of desorption temperature, while preserving similar gravimetric density and Bulk modulus as of pure MgH2 system. The electron localization function plot and population analysis illustrate that the bond between Dopant-Hydrogen is mainly covalent, which weaken the Mg-Hydrogen bonds. Overall we observed that Al as dopant is suitable and surface doping can help in lowering the desorption temperature. So layer dependent doping studies can help to find the best possible reversible hydride based hydrogen storage materials.

We investigate the interaction of molecular hydrogen with light element based ndoped hexagonal boron nitride (h-BN) nanostructures and moreover explore the bond exchange mechanism for spillover of atomic hydrogen using dispersion-corrected density functional theory (DFT-D) calculations. A number of doped configurations were tested and it has been found that co-doping of C and O on h-BN sheet significantly increases the adsorption energy of molecular H 2 . The charge transfer from the n-doped h-BN surface to H 2 is found to be the reason for the higher interactions that boosted the binding energy. In addition, the doped h-BN surfaces act as catalysts and dissociate the H 2 molecule with very low activation barrier, but the migration of the resulting H atoms on the surface requires high energy. In order to facilitate easy and fast migration of H atoms, we introduce the bond exchange mechanism using external mediators i.e. borane (BH 3 ) and gallane (GaH 3 ) molecules which serve as a secondary catalysts and help in lowering the migration barrier, leading to the formation of hydrogenated surface. The partially hydrogenated surface in turn can also act as a hydrogen storage material, with a higher propensity to adsorb hydrogen molecules when compared to the unhydrogenated surface. Hence the surface proposed in this work can be used to store substantial quantity of hydrogen as energy source with easy adsorption and desorption kinetics.