Cargando…

Relaxation Phenomena in Chitosan-Au Nanoparticle Thin Films

Chitosan–gold nanoparticle (CS/AuNP) thin films were synthesized through the chemical reduction of HAuCl(4) in sodium citrate/chitosan solutions. The dielectric and dynamic mechanical behaviors of CS/AuNP films have been investigated as a function of moisture and HAuCl(4) content. Two relaxation pro...

Descripción completa

Detalles Bibliográficos
Autores principales: Strupiechonski, Elodie, Moreno-Ríos, Marisa, Ávila-Dávila, Erika O., Román-Doval, Ramón, Prokhorov, Evgeny, Kovalenko, Yuriy, Zárate-Triviño, Diana G., Medina, Dora I., Luna-Barcenas, Gabriel
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8512657/
https://www.ncbi.nlm.nih.gov/pubmed/34641030
http://dx.doi.org/10.3390/polym13193214
_version_ 1784583047313620992
author Strupiechonski, Elodie
Moreno-Ríos, Marisa
Ávila-Dávila, Erika O.
Román-Doval, Ramón
Prokhorov, Evgeny
Kovalenko, Yuriy
Zárate-Triviño, Diana G.
Medina, Dora I.
Luna-Barcenas, Gabriel
author_facet Strupiechonski, Elodie
Moreno-Ríos, Marisa
Ávila-Dávila, Erika O.
Román-Doval, Ramón
Prokhorov, Evgeny
Kovalenko, Yuriy
Zárate-Triviño, Diana G.
Medina, Dora I.
Luna-Barcenas, Gabriel
author_sort Strupiechonski, Elodie
collection PubMed
description Chitosan–gold nanoparticle (CS/AuNP) thin films were synthesized through the chemical reduction of HAuCl(4) in sodium citrate/chitosan solutions. The dielectric and dynamic mechanical behaviors of CS/AuNP films have been investigated as a function of moisture and HAuCl(4) content. Two relaxation processes in the nanocomposites have been observed. The α-relaxation process is related to a glass transition in wet CS/AuNP films. However, in dry composites (with 0.2 wt% of moisture content), the glass transition vanished. A second relaxation process was observed from 70 °C to the onset of thermal degradation (160 °C) in wet films and from 33 °C to the onset of degradation in dry films. This relaxation is identified as the σ-relaxation and may be related to the local diffusion process of ions between high potential barriers in disordered systems. The α- and σ-relaxation processes are affected by the HAuCl(4) content of the solutions from which films were obtained because of the interaction between CS, sodium succinate, and gold nanoparticles. With about 0.6 mM of HAuCl(4), the conductivity of both wet and dry films sharply increased by six orders, corresponding to the percolation effect, which may be related to the appearance of a conductivity pathway between AuNPs, HAuCl(4), and NaCl.
format Online
Article
Text
id pubmed-8512657
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher MDPI
record_format MEDLINE/PubMed
spelling pubmed-85126572021-10-14 Relaxation Phenomena in Chitosan-Au Nanoparticle Thin Films Strupiechonski, Elodie Moreno-Ríos, Marisa Ávila-Dávila, Erika O. Román-Doval, Ramón Prokhorov, Evgeny Kovalenko, Yuriy Zárate-Triviño, Diana G. Medina, Dora I. Luna-Barcenas, Gabriel Polymers (Basel) Article Chitosan–gold nanoparticle (CS/AuNP) thin films were synthesized through the chemical reduction of HAuCl(4) in sodium citrate/chitosan solutions. The dielectric and dynamic mechanical behaviors of CS/AuNP films have been investigated as a function of moisture and HAuCl(4) content. Two relaxation processes in the nanocomposites have been observed. The α-relaxation process is related to a glass transition in wet CS/AuNP films. However, in dry composites (with 0.2 wt% of moisture content), the glass transition vanished. A second relaxation process was observed from 70 °C to the onset of thermal degradation (160 °C) in wet films and from 33 °C to the onset of degradation in dry films. This relaxation is identified as the σ-relaxation and may be related to the local diffusion process of ions between high potential barriers in disordered systems. The α- and σ-relaxation processes are affected by the HAuCl(4) content of the solutions from which films were obtained because of the interaction between CS, sodium succinate, and gold nanoparticles. With about 0.6 mM of HAuCl(4), the conductivity of both wet and dry films sharply increased by six orders, corresponding to the percolation effect, which may be related to the appearance of a conductivity pathway between AuNPs, HAuCl(4), and NaCl. MDPI 2021-09-23 /pmc/articles/PMC8512657/ /pubmed/34641030 http://dx.doi.org/10.3390/polym13193214 Text en © 2021 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Strupiechonski, Elodie
Moreno-Ríos, Marisa
Ávila-Dávila, Erika O.
Román-Doval, Ramón
Prokhorov, Evgeny
Kovalenko, Yuriy
Zárate-Triviño, Diana G.
Medina, Dora I.
Luna-Barcenas, Gabriel
Relaxation Phenomena in Chitosan-Au Nanoparticle Thin Films
title Relaxation Phenomena in Chitosan-Au Nanoparticle Thin Films
title_full Relaxation Phenomena in Chitosan-Au Nanoparticle Thin Films
title_fullStr Relaxation Phenomena in Chitosan-Au Nanoparticle Thin Films
title_full_unstemmed Relaxation Phenomena in Chitosan-Au Nanoparticle Thin Films
title_short Relaxation Phenomena in Chitosan-Au Nanoparticle Thin Films
title_sort relaxation phenomena in chitosan-au nanoparticle thin films
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8512657/
https://www.ncbi.nlm.nih.gov/pubmed/34641030
http://dx.doi.org/10.3390/polym13193214
work_keys_str_mv AT strupiechonskielodie relaxationphenomenainchitosanaunanoparticlethinfilms
AT morenoriosmarisa relaxationphenomenainchitosanaunanoparticlethinfilms
AT aviladavilaerikao relaxationphenomenainchitosanaunanoparticlethinfilms
AT romandovalramon relaxationphenomenainchitosanaunanoparticlethinfilms
AT prokhorovevgeny relaxationphenomenainchitosanaunanoparticlethinfilms
AT kovalenkoyuriy relaxationphenomenainchitosanaunanoparticlethinfilms
AT zaratetrivinodianag relaxationphenomenainchitosanaunanoparticlethinfilms
AT medinadorai relaxationphenomenainchitosanaunanoparticlethinfilms
AT lunabarcenasgabriel relaxationphenomenainchitosanaunanoparticlethinfilms