TY - JOUR

T1 - Structure and ionic transport properties of AgI 1- xBr x within single-wall carbon nanotubes from molecular dynamics simulation

AU - Gotlib, Igor Yu

AU - Ivanov-Schitz, Alexey K.

AU - Murin, Igor V.

AU - Petrov, Andrey V.

AU - Zakalyukin, Ruslan M.

N1 - Copyright: Copyright 2012 Elsevier B.V., All rights reserved.

PY - 2012/9/13

Y1 - 2012/9/13

N2 - Morphologies of AgI 1-xBr x (0 ≥ x ≥ 1) nanocrystalline structures formed in carbon single-wall nanotubes (SWNT), of diameter d = 11.5-17.6 Å, have been investigated by molecular dynamics simulation. For AgI 1-xBr x in a (10, 10) carbon SWNT (d = 13.54 Å), ionic motion characteristics at different temperatures have been studied. Calculations confirm the experimentally based suggestion that structural differences between AgI and AgBr in carbon SWNTs are less pronounced than in the bulk crystals. According to the simulation results, in tubes taken out from the melt, AgBr and AgI 1-xBr x tend to form hexagonal nanotubes after annealing, similar to those formed by AgI. A superionic state, with significant silver ion mobility against a stable anion sublattice, can be observed in the simulated AgI 1-xBr x@SWNT; the superionic conduction temperature range shifts downward with increasing bromine content. At temperatures below and just above the nanocrystal melting point, ion migration is faster in more bromine-rich AgI 1-xBr x@SWNT systems, while at T ≥ 1000 K, the composition dependence of ion diffusion coefficients is much less pronounced. Just as in AgI@SWNT systems, the ion transport characteristics change significantly with a transition from single-wall AgI 1-xBr x nanotubes in carbon SWNTs to structures with extra ions in the tube center.

AB - Morphologies of AgI 1-xBr x (0 ≥ x ≥ 1) nanocrystalline structures formed in carbon single-wall nanotubes (SWNT), of diameter d = 11.5-17.6 Å, have been investigated by molecular dynamics simulation. For AgI 1-xBr x in a (10, 10) carbon SWNT (d = 13.54 Å), ionic motion characteristics at different temperatures have been studied. Calculations confirm the experimentally based suggestion that structural differences between AgI and AgBr in carbon SWNTs are less pronounced than in the bulk crystals. According to the simulation results, in tubes taken out from the melt, AgBr and AgI 1-xBr x tend to form hexagonal nanotubes after annealing, similar to those formed by AgI. A superionic state, with significant silver ion mobility against a stable anion sublattice, can be observed in the simulated AgI 1-xBr x@SWNT; the superionic conduction temperature range shifts downward with increasing bromine content. At temperatures below and just above the nanocrystal melting point, ion migration is faster in more bromine-rich AgI 1-xBr x@SWNT systems, while at T ≥ 1000 K, the composition dependence of ion diffusion coefficients is much less pronounced. Just as in AgI@SWNT systems, the ion transport characteristics change significantly with a transition from single-wall AgI 1-xBr x nanotubes in carbon SWNTs to structures with extra ions in the tube center.

UR - http://www.scopus.com/inward/record.url?scp=84866389806&partnerID=8YFLogxK

U2 - 10.1021/jp305518t

DO - 10.1021/jp305518t

M3 - Article

AN - SCOPUS:84866389806

VL - 116

SP - 19554

EP - 19570

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 36

ER -