화학공학소재연구정보센터
Solid State Ionics, Vol.188, No.1, 6-14, 2011
Computer simulation of ionic transport in silver iodide within carbon nanotubes
Filling of carbon single-wall nanotubes (SWNTs), of diameter d = 11.5-15 angstrom. by silver iodide from the melt is modeled by molecular dynamics. Formation of Agl inorganic nanotube (INT) structures in the SWNTs on cooling, and ion diffusion in Agl within the tubes (Agl@SWNT) at 500-1200 K are studied. Dependence of Agl@SWNT structure on carbon SWNT geometry is examined. For d <= 14.2 angstrom, a single-wall Agl INT is formed within the carbon tube, with structure (geometry) depending on d; in wider tubes, there are extra silver and iodine ions in the central region. The calculated diffusion coefficients of silver and iodine ions and their diffusion activation energies depend on the nanotube geometry. Ion mobilities within carbon SWNTs are significantly lower, and diffusion activation energies, higher than in the bulk phase of Agl, especially in narrow tubes. In the (11,11) carbon SWNT, the widest among those simulated, the activation energy for silver ion diffusion becomes close to the "bulk" value, while for iodine ions, larger in size, the difference remains. (C) 2010 Elsevier B.V. All rights reserved.