Voltammetric study of PrF3:Sr2+ and NdF3:Ba2+ solid electrolytes

Abstract

Studies of single crystals of nonstoichiometric fluorides of PrF 3 :Sr 2+ and NdF 3 :Ba 2+ in contact with a Pt electrode were carried out using the method of voltammetry with a linear potential sweep, chrono amperometry, and cyclic voltammetry. The reaction of gaseous oxygen reduction (GOR) at the PrF 3 :Sr 2+ /Pt interface was accompanied by appearance of mobile oxygen forms. The catalytic activity of PrF 3 :Sr 2+ with respect to gaseous oxygen, same as CeF 3 :Sr 2+ , can be explained by variable valency of praseodymium and cerium fluoride, which creates opportunities for using them in oxygen and oxygen-containing gas sensors. The GOR reaction at the NdF 3 :Ba 2+ /Pt interface appeared as a result of anodic polarization. After charging at E = 3.2 V, the NdF 3 :Ba 2+ single crystal was successfully used for fluorination of Sb and Ag. NdF 3 :Ba 2+ is most promising in devices based on reactions with participation of mobile fluoride ion in solid electrolytes, particularly, for generation of gaseous fluorine.