Theoretical study of electronic structure of boron-nitride 8,0 15TH PHYSICAL CHEMISTRY CONFERENC

In recent years, many research interests were focused on boron nitride nanotubes (BNNTs), as isomorphic analog of the carbon nanotubes (CNTs), due to their unique and important properties ideal for structural and electronic applications [1]. There are many similarities between CNTs and BNNTs, themain difference being that BNNTs are viewed as always being semiconductors with almost constant band gap nearly independent of tubular diameter andchirality [1], while CNTs can present metallic or semiconductor behavior [2]. Many studies have demonstrated that electronicand structural properties of BNNTs can be significantly influenced by dopant atom [3]. Up to now, doping BNNTs with different types of atoms isbelieved to be an effective way to enhance hydrogen storage capacity at ambient temperature [4]. In addition to increasing adsorption energy of H2, metaldoping also increases the effective surface area available for adsorption in some cases. Hydrogen adsorption then goes beyond a single monolayer,increasing the volumetric and gravimetric hydrogen densities accordingly [5]. In 2002, Pokropivnyi suggested that the BNNTs could be transformed inton- or p-type semiconductors by ionic doping [6]. This might enable property control to meet different application requirements. Here, we determine geometries and electronic structures of zigzag (8,0) BNNT with various distributions of dopant atoms. Influence of C-doping on different sites of a zigzag (8,0) BNNT model is examined based on structural parameters such as optimized bond lengths anddipole moments. From the set of theories with thecapability of describing local variations of bonding, the quantum theory of atoms in molecules (QTAIM)approach [7] was also selected for the current study.