Electrical potential near hydrated surface of ordered mesoporous molecular sieves assessed by EPR of molecular pH-probes

Journal article
(Original article)


Publication Details

Author(s): Kovaleva EG, Molochnikov LS, Golovkina EL, Hartmann M, Kirilyuk IA, Grigoriev IA
Journal: Microporous and Mesoporous Materials
Publisher: Elsevier
Publication year: 2015
Volume: 203
Pages range: 1-7
ISSN: 1387-1811
Language: English


Abstract


Some of the most important parameters of mesoporous materials are Stem potential of double electrical layer (DEL) and surface charge because of the pivotal role they play in the adsorption of charged molecular species. There are not any conventional and easy-to-perform techniques used to measure Stern potential in porous systems. The purpose of this work is to measure Stern potential in a specific case, i.e., practically cylindrical nanosized hydrated channels of the mesoporous molecular sieves (MMS) MCM-41 and SBA-15 with channel diameters ranging from 2.3 to 8.1 nm using pH-sensitive nitroxide radicals (NR). A technique for direct measurement of the near-surface (Stern) potential using pH-sensitive NR was developed. Negative and positive values of Stern potential for the positively and negatively charged surface of MMS channels were found. The ranges of pH of external solution for the near-zero charge, boost-charging of the channel surface and for dissociation of functional groups in the MMS studied were found. (C) 2014 Elsevier Inc. All rights reserved.



FAU Authors / FAU Editors

Hartmann, Martin Prof. Dr.
Professur für Katalyse


Additional Organisation
Interdisziplinäres Zentrum Erlangen Catalysis Resource Center (ECRC)


External institutions with authors

Russian Academy of Sciences / Росси́йская акаде́мия нау́к (RAS)
Ural Federal University B.N. Yeltsin
Ural State Forest Engineering University (USFEU) / Уральский государственный лесотехнический университет (УГЛТУ)


How to cite

APA:
Kovaleva, E.G., Molochnikov, L.S., Golovkina, E.L., Hartmann, M., Kirilyuk, I.A., & Grigoriev, I.A. (2015). Electrical potential near hydrated surface of ordered mesoporous molecular sieves assessed by EPR of molecular pH-probes. Microporous and Mesoporous Materials, 203, 1-7. https://dx.doi.org/10.1016/j.micromeso.2014.10.010

MLA:
Kovaleva, Elena G., et al. "Electrical potential near hydrated surface of ordered mesoporous molecular sieves assessed by EPR of molecular pH-probes." Microporous and Mesoporous Materials 203 (2015): 1-7.

BibTeX: 

Last updated on 2018-10-08 at 03:09