New proton conducting materials for technical applications: What can we learn from solid state NMR studies?

• Published in: Solid state nuclear magnetic resonance Vol. 40; no. 4; pp. 127 - 133
• Main Author: Graf, Robert
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 01.11.2011
• Subjects: Amphoterics; Bonding; Conduction; Dynamic tests; Exchange NMR; Hydrogen bonded networks; Hydrogen bonding; Magic angle spinning; Molecular dynamics; Networks; Nuclear magnetic resonance; Proton conduction; Solid state; Solid State NMR; Variable temperature MAS; Solid State NMR; Magic angle spinning; Proton conduction; Molecular dynamics; Variable temperature MAS; Hydrogen bonded networks; Exchange NMR
• ISSN: 0926-2040; 1527-3326
• DOI: 10.1016/j.ssnmr.2011.09.003

Many novel proton conducting materials are based on complex hydrogen bonding networks of amphoteric hydrogen bonded moieties. Solid state NMR provides unique methods to study the properties of such network and specific proton conduction mechanisms in detail. In particular 1H solid state NMR techniques under fast magic angle spinning are powerful tools in this area. Site specific studies of the dynamic behavior via variable temperature 1H MAS measurements provide insight in the thermodynamics of the hydrogen bonding as well as activation energies for the proton transfer between the amphoteric sites. On macroscopic length scales, pulsed field gradient NMR experiments are able to determine the proton mobility and the contribution of different conduction mechanisms. In this article, aspects of recent solid state NMR studies in the field are reviewed and typical experimental methods as well as their possible outcome are discussed. [Display omitted]