Suitability of boron-nitride single-walled nanotubes as fluid-flow conduits in nano-valve applications

Molecular-level simulations are used to examine the suitability of boron-nitride single-walled nanotubes (SWNTs) as fluid-flow conduits in the nano-valve applications based on a molecular-mono-layer functionalized silicon cantilever. The interaction between the constituent atoms in the nanotubes is modeled using the Universal Force Field inter-atomic potential. Key functional requirements (a large range of nanotube radii with a stable circular cross section, a low level of strain energy in the nanotube at the onset of bending-induced buckling, relatively high compliance with respect to the radial breathing mode and a low value of nanotube/fluid-molecule binding energy) have been identified for nanotube fluid-flow conduits. The results obtained suggest that boron-nitride SWNTs do not offer any significant functional advantage over their carbon-based counterparts when used in fluid-flow conduit applications. The results also suggests that several of the nanotube properties obtained through the use of the Universal Force Field are quite comparable to their counterparts based on the first-principles quantum-mechanical calculations.