Electrochemical fluorination of perovskite type BaFeO_2.5

Here we report on the first electrochemical fluorination exemplarily performed on perovskite type BaFeO_2.5. A cell setup of the type BaFeO_2.5 II La_0.9Ba_0.1F_2.9 II MF_x (with MF_x being MgF₂ and CeF₃) was used to perform the reaction, charging the cell up to voltages of about 4 V. Formation of a compound of approximate composition BaFeO_2.5F_∼0.5 was observed, in agreement with diffraction studies of the independently performed chemically fluorinated compound using F₂ gas, and also possessing a capacity which is close to the theoretical capacity of the material. This new method gives an alternative towards the use of highly reactive and toxic F₂ gas, and provides potential in adjusting the chemical potential for oxidative chemical fluorinations.