Dehydration-rehydration characteristics of Nafion-H, Nafion-H supported onsilica and Nafion-H silica nanocomposite catalysts studied by Infrared Microscopy

Authors
Palinko, I Torok, B Prakash, GKS Olah, GA
Citation
I. Palinko et al., Dehydration-rehydration characteristics of Nafion-H, Nafion-H supported onsilica and Nafion-H silica nanocomposite catalysts studied by Infrared Microscopy, J MOL STRUC, 483, 1999, pp. 29-32
Citations number
4
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
JOURNAL OF MOLECULAR STRUCTURE
ISSN journal
00222860 → ACNP
Volume
483
Year of publication
1999
Pages
29 - 32
Database
ISI
SICI code
0022-2860(19990525)483:<29:DCONNS>2.0.ZU;2-#
Abstract
Dehydration-rehydration characteristics of Nafion-H, silica-supported Nafio n-H and two types of Nafion-H silica nanocomposites were studied by infrare d microscopy working in the reflectance mode. The as received as well as th e variously pretreated samples (evacuation at 298, 378 and 423 K) and the r ehydrated samples were investigated in the mid IR range. Reversible changes in the OH region of the supported and the composite substances were observ ed depending on the temperature of pretreatment. Pretreatment at 423 K lead to more extensive changes in Nafion-H, i.e., to the loss of certain amount of -SO2OH groups through irreversible desulfonation/dehydroxylation. (C) 1 999 Elsevier Science B.V. All rights reserved.