The proton conduction and superionic phase transition of cesium dihydrogen phosphate, CsH 2 PO 4 (CDP), were investigated under various humid conditions to evaluate the applicability of a CsH 2 PO 4 solid electrolyte to an intermediate temperature fuel cell operating between 230°C and 300°C. The phase stability, superionic phase transition, and reversibility of dehydration of CsH 2 PO 4 were evaluated under different ambient water vapor concentrations, from 0 to 90 mol%, through the measurements of conductivity. The dependence of conductivity on the water vapor concentration and the demonstrated reversibility of dehydration clearly showed the range in which CsH 2 PO 4 is applicable to the intermediate temperature fuel cell. Additionally, we evaluated the protonic transport number of CsH 2 PO 4 , which was almost unity, and demonstrated fuel cell operation at 250°C using a single cell fabricated with the CsH 2 PO 4 electrolyte.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.