Little known heterostructures “compound alkaline electrolyte – electron conductor”: hydroxide ion as a proton acceptor and an electrochemically active species
Yu. M. Baikov, E. I. Nikulin, B. T. Melekh, L. G. Baikova
The family of complex materials such as crystalline hydrates and solid eutectics, on the base of hydroxides of alkaline metals (Na, K, Rb, Cs) has been studied thoroughly from the general physico-chemical point of view. However, the high proton conductivity of the members of this family has been revealed on for the last few years. Correspondingly there was no information on the electrochemical activity of heterostructures “alkaline proton | electron conductor”. In our opinion the crucial reason for this objectionable approach of world ionic community to whole alkaline-hydroxide-family was due to dramatic history of arising and then falling of interest in individual alkaline hydroxides. The key aim of the paper is to present our results of the development of solid and molten hydroxide materials which are good proton conductors at intermediate / room temperatures (450 < T < 250K) and low-humidity or even anhydrous conditions, as well as are electrochemically active in MEA with Ti, TiFe, Sn and Si. The main experimental results and informal discussions on necessary further progress in fundamental understanding of the underlying proton conduction mechanisms are collected now on website http://www.solidionic.com.
Accepted at EMRS 2012 as oral.