Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/341176
Type: Artigo
Title: Imaging ion pairs forming structural arrangements in interfacial regions
Author: Teschke, Omar
Castro, Jose Roberto de
Soares, David Mendez
Abstract: A technique to image ion pairs in solution is reported. We investigated structural and dynamic properties of ion-pair distributions deposited on highly oriented pyrolytic graphite (HOPG) surfaces in electrolyte solutions. Atomic force microscopy images of HOPG immersed in NaCl and KCl solutions display regular arrangements on top of the hexagonal carbon rings forming the HOPG atomic structure. These arrangements are the result of the low value of the aqueous interfacial dielectric constant (epsilon(r) approximate to 3-11). The measured ion-pair radius is a function of the salt present in the solution; for KCl, the ion-pair radius is equal or smaller than 0.42 nm; for NaCl, the ion-pair radius is 0.36 nm. A comparison of these values with their crystalline lattice dimensions indicates that both KCl and NaCl ion pairs in solution at the HOPG/solution interfacial region exist as tight contact ion pairs in quasistationary distributions. The NaCl ion-pair distribution forms an aligned arrangement, and the KCl distribution is formed by intercalated pairs.
Subject: Dinâmica molecular
Química de superfície
Interferometria
Molecular dynamics
Surface chemistry
Interferometry
Country: Estados Unidos
Editor: American Chemical Society
Rights: fechado
Identifier DOI: 10.1021/acsomega.9b02299
Address: https://pubs.acs.org/doi/10.1021/acsomega.9b02299
Date Issue: 2019
Appears in Collections:IFGW - Artigos e Outros Documentos

Files in This Item:
File SizeFormat 
000488852700041.pdf10.29 MBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.