Ammonia Adsorption on SiC Nanotubes: A Density Functional Theory Investigation

Abstract

The adsorption of NH3 on a (5, 0) single-walled SiC nanotube is studied by using the density functional theory approach. The silicon atoms in sites on SiCNT surface is the most stable adsorption site for N pointing of NH3 toward the nanotube surface, with a binding energy of −1.36 eV (−31.35 kcal mol−1) and a Si–N binding distance of 1.972 Å. We also have tested the stability of the NH3-adsorbed SiCNT with ab initio molecular dynamics calculations, which have been carried out at room temperature. Furthermore, the adsorption of NH3 on the single-walled carbon nanotubes has been investigated. Our first-principles calculations predict that the NH3 adsorptive capability of silicon carbide nanotubes is much better than that of carbon nanotubes. This demonstrates that SiCNTs could be a promising material for gas detection and energy storage.