| During the development of catalysts and adsorbents of the chemical engineering, it is a basic theoretical subject to research the interaction between the molecule/atom and the material surface. It involves a multidisciplinary research field, as well as the chemical catalysis reaction, gas adsorption and many actual industrial problems. The behaviors of the adsorption and dissociation of molecule/atom on the surface is great significant to understand the surface chemical reaction. In the experiment, it is difficult from the atomic and quantum level to understand the behaviors of the molecule/atom interacted with the surface, involving bonding, charge transferring or orbital hybridization. Base on the first-principle, it can be from the electronic level revealed the microscopic mechanism of the interaction between molecule/atom and surface, providing a theoretical basis for the development of catalysts and adsorbents. In this paper, two typical systems (the interactions of the molecule/atom and the surface, and the hydrogen molecule and light elements nano-material) are chosed to discuss the electronic structures (density of state, band, charge location, et al.) and the bonding mechanism between molecue/atom and surface. The main conclusions are as follows: (1) The interaction of oxygen atom/molecule and the Pb (111) films is systematically discussed. The calculated results indicate that adiabatic DFT calculation leads to reliable results for the O2/Pb (111) system. In addition, many properties of O/Pb (111) system such as the adsorption energies or work-functions show bilayer oscillation behaviors because of the quantum size effect. In further, many surface oxidation processes such as diffusion, penetration, and dissociation are proved to be modulated by the quantum size effect.(2) The adsorption of O2molecule on the Sn (111)2×2surface is investigated. Based on this, the adsorption behaviors of O2on X (111)(X=Si, Ge, Sn, Pb) surfaces are compared and analyzed. The results indicate that the chemisorbed adsorption precursor states for O2are identified to be along the parallel and vertical channels. In addition, the surface reconstructions of Sn (111) induced by oxygen adsorption are studied. The most stable adsorption channels of O2on X (111)(X=Si, Ge, Sn, Pb) are found. The surface reconstructions and electron distributions along the most stable adsorption channels are discussed and compared. The result show that the O2adsorption ability is gradually weakened with the enhancement of metallicity and the amount of charge transfer decreases.(3) The first-principles calculations are performed to investigate the adsorption of hydrogen on a Li-decorated hybridzed boron nitride and graphene domians of (BN)xC1-x complexes for (a)x=1,(b)x=0.25,(c)x=0.5, (d)x=0.75,(e)x=0,(f)B0.125C0.875. The hybridization between Li atom and substrates are investigated and the results show that nitrogen atoms in the substrate planes can increase the hybridization between the2p orbitals of Li and the orbitals of H2. The discussion of most stable adsorption sites of nth hydrogen molecules on lithium-decorated (BN)xC1-x complexes are systematically discussed, which indicates that the most stable adsorption sites are decided by the charge localization and the hydrogen molecules are favorable to locate above the C-C bonds besides the Li atom. Based on this, the hydrogen storage on (BN)xC1-x complexes are investigated, indicating that the Li-decorated (BN)0.25C0.75complex has good thermal stability and is feasible to dehydrogeneration and can achieve a high hydrogen storage amount of8.7wt%. |
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