This communication outlines the use of HFC 134a and HFC 32 in both the liquid and supercritical states. The comparatively mild critical conditions are used to show that both of these solvents are important for studying electrochemical processes in the supercritical state. The higher polarity of these media in the supercritical state circumvent many of the problems associated with solubility, conductivity and ion adsorption on the electrode surface observed with other supercritical media also. The unprecedented wide potential window of HFC 134a is demonstrated and utilised for the oxidation of Xe and Cs+.