Direct Measurement of Single Ionic Drift Velocities in Electrolyte Solutions. An NMR Method

Abstract

Abstract The theoretical and experimental principles of a novel method for the direct and rapid measurement of single ionic drift velocities in electrolytes are presented. The method is based on an NMR flow measuring technique and the velocity information is obtained through the observation of the spin‐echo amplitude in the presence of a pulsed magnetic field gradient and a pulsed electric field. It allows the determination of ionic mobilities and transference numbers in a more “direct” way than the classical electrochemical methods. First experimental results for (C 2 H 5 ) 4 N + ‐ions in aqueous solution are shown. Advantages, disadvantages and possible applications of this new NMR method in electrochemistry are discussed. It seems that the method has special advantages for measurements of electrical transport data in solutions of mixed electrolytes. The observation ot solvent motions in conducting electrolyte solutions could also be a possible application.