Diffusion in Solid Proton Conductors: Theoretical Aspects and Nuclear Magnetic Resonance Analysis

Abstract

Water behavior in solid proton conductors is a considerably complex phenomenon. However, the knowledge of transport and diffusivity inside electrolytes is an important requirement for many applications. Extensive efforts have been made in terms of modeling water transport and its management. Accurate measurements of diffusion are required to validate these models and to optimize the performance of solid proton conductors.The focus of this chapter is the theoretical approach together with the use of nuclear magnetic resonance (NMR) techniques for the understanding of diffusion phenomena in solid proton conductors. The basic principles and the main NMR methods will be also discussed.

Structural Analysis and Conduction Mechanisms in Polycrystalline Zinc Hydroxide Nitrate

“…Proton hopping occurs from a hydronium (H 3 O + ), and the excessive proton charge travels through networks generated between neighboring water molecules. The proton-transfer process of a solvated molecule between two water molecules can occur on the order of a few picoseconds …”

“…The proton-transfer process of a solvated molecule between two water molecules can occur on the order of a few picoseconds. 44 The conductivity for Z 5 HN at 25 °C is frequencyindependent over a broad range. This behavior can be described as a long-range proton (H + ) hopping where the protons should have the same potential along the entire mobility pathway.…”