A pressure-tight electrode for cyclic voltammetry measurements in liquefied gases as solvents

The construction of an apparatus for cyclic voltammetry measurements in solvents with elevated vapour pressures is described. The results revealed the possibility of determining redox potentials in liquid SO2 as solvent at room temperature and above. The container, which can withstand the vapour pressure of liquid SO2 and the electrodes were home-made, mainly from commercially available components. A series of measurements have been performed in order to evaluate the redox behaviour of thianthrene in liquid SO2 and the influence of temperature on the potentials.

► We constructed a cyclic voltammetry apparatus set including the container and the electrodes.
► We evaluated the redox potential of thianthrene in acetonitrile and in liquid SO2 using the apparatus.
► The redox potential of thianthrene relative to ferrocene was almost identical regardless the solvent used.
► The apparatus set allowed measurements in liquid SO2 ranging from −63 °C to room temperature.