Hydroxide ion Conduction Mechanism in Mg-Al CO32− Layered Double Hydroxide

Ionic conduction mechanism of Mg-Al layered double hydroxides (LDHs) intercalated with CO32− (Mg-Al LDH) was studied. The electromotive force for the water vapor concentration cell using LDH as electrolyte showed partial pressure dependence and obeyed Nernst equation, indicating that hydroxide ion transport number is almost unity. ionic conductivity Mg(OH)2, MgCO3 Al2(CO3)3 also examined. Only high order 10−4 S cm−1 under 80% relative humidity, suggesting an conducting material related to generation carrier by interaction water. To discuss mechanism, having deuterium interlayer LDH(D2O)) prepared. After adsorbed molecules on surface LDH(D2O) were removed drying, DC polarization test dried absorbance attributed O-D-stretching band powder at around positively charged electrode larger than before polarization, in a channel. Keywords: Layered Double Hydroxide, Hydroxide Ion Conductor, Conduction Mechanism, Deuterium Water Replacement