Abstract:The adsorption of H2 on two kinds of Mg3N2(110) crystal surface is studied by first principles. Adsorption sites, adsorption energy, and the electronic structure of the Mg3N2(110)/H2 systems are calculated separately. It is found that H2 is mainly adsorbed as chemical adsorption, on these sites the H2 molecules are dissociated and the H atoms tend to the top of two N, respectively, forming two NH, or the H atoms tend to the same N forming one NH2. There are also some physical adsorption sites. One of the bridge sites of Mg3N2(110) surface is more favorable than the other sites. On this site, H atoms tend to the top of two N, forming two NH. This process belongs to strong chemical adsorption. The interaction between H2 molecule and Mg3N2(110) surface is mainly due to the overlap-hybridization among H 1s, N 2s, and N 2p states, covalent bonds are formed between the N and H atoms.