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Studying Proton Mobility in Zeolites by Varying Temperature Infrared Spectroscopy

We report a varying temperature infrared spectroscopic (VTIR) study with partial deuterium isotopic exchange as a method for characterizing proton mobility in acidic materials. This VTIR technique permits the estimation of activation energies for proton diffusion. Different acidic materials comprisi...

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Autores principales: Losch, Pit, Joshi, Hrishikesh, Stegmann, Niklas, Vozniuk, Olena, Schmidt, Wolfgang
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6749307/
https://www.ncbi.nlm.nih.gov/pubmed/31484400
http://dx.doi.org/10.3390/molecules24173199
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author Losch, Pit
Joshi, Hrishikesh
Stegmann, Niklas
Vozniuk, Olena
Schmidt, Wolfgang
author_facet Losch, Pit
Joshi, Hrishikesh
Stegmann, Niklas
Vozniuk, Olena
Schmidt, Wolfgang
author_sort Losch, Pit
collection PubMed
description We report a varying temperature infrared spectroscopic (VTIR) study with partial deuterium isotopic exchange as a method for characterizing proton mobility in acidic materials. This VTIR technique permits the estimation of activation energies for proton diffusion. Different acidic materials comprising classical proton-conducting materials, such as transition metal phosphates and sulfonated solids, as well as different zeolites, are tested with this new method. The applicability of the method is thus extended to a vast library of materials. Its underlying principles and assumptions are clearly presented herein. Depending on the temperature ranges, different activation energies for proton transfer are observed irrespective of the different materials. In addition to the well-studied transition metal phosphates, Si-rich zeolites appear to be promising proton-transfer materials (with E(act) < 40 kJ mol(−1)) for application in high-temperature (>150 °C) PEM fuel cells. They significantly outperform Nafion and sulfonated silica, which exhibit higher activation energies with E(act) ~ 50 and 120 kJ mol(−1), respectively.
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spelling pubmed-67493072019-09-27 Studying Proton Mobility in Zeolites by Varying Temperature Infrared Spectroscopy Losch, Pit Joshi, Hrishikesh Stegmann, Niklas Vozniuk, Olena Schmidt, Wolfgang Molecules Article We report a varying temperature infrared spectroscopic (VTIR) study with partial deuterium isotopic exchange as a method for characterizing proton mobility in acidic materials. This VTIR technique permits the estimation of activation energies for proton diffusion. Different acidic materials comprising classical proton-conducting materials, such as transition metal phosphates and sulfonated solids, as well as different zeolites, are tested with this new method. The applicability of the method is thus extended to a vast library of materials. Its underlying principles and assumptions are clearly presented herein. Depending on the temperature ranges, different activation energies for proton transfer are observed irrespective of the different materials. In addition to the well-studied transition metal phosphates, Si-rich zeolites appear to be promising proton-transfer materials (with E(act) < 40 kJ mol(−1)) for application in high-temperature (>150 °C) PEM fuel cells. They significantly outperform Nafion and sulfonated silica, which exhibit higher activation energies with E(act) ~ 50 and 120 kJ mol(−1), respectively. MDPI 2019-09-03 /pmc/articles/PMC6749307/ /pubmed/31484400 http://dx.doi.org/10.3390/molecules24173199 Text en © 2019 by the authors. 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 (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Losch, Pit
Joshi, Hrishikesh
Stegmann, Niklas
Vozniuk, Olena
Schmidt, Wolfgang
Studying Proton Mobility in Zeolites by Varying Temperature Infrared Spectroscopy
title Studying Proton Mobility in Zeolites by Varying Temperature Infrared Spectroscopy
title_full Studying Proton Mobility in Zeolites by Varying Temperature Infrared Spectroscopy
title_fullStr Studying Proton Mobility in Zeolites by Varying Temperature Infrared Spectroscopy
title_full_unstemmed Studying Proton Mobility in Zeolites by Varying Temperature Infrared Spectroscopy
title_short Studying Proton Mobility in Zeolites by Varying Temperature Infrared Spectroscopy
title_sort studying proton mobility in zeolites by varying temperature infrared spectroscopy
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6749307/
https://www.ncbi.nlm.nih.gov/pubmed/31484400
http://dx.doi.org/10.3390/molecules24173199
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