A study of the electrical double layer at PbO2 in aqueous KNO3 electrolyte

Abstract

The impedance of α- and β-PbO2 electrodes in aqueous KNO3 has been measured as a function of bias potential and ionic strength. Differential capacitance data are reported for electrolytes 0.307-0.0043 mol l-1. Integration of the capacitance curves yielded charge density as a function of potential. At constant charge density, the potential of the electrode, measured with reference to SCE is an approximately linear function of the chemical potential. The value of Ez is 0.81±0.01 V (SCE) for α-PbO2 and 0.905±0.01 V. (SCE) for β-PbO2. The system resembles mercury in the general features of its behaviour but differences occur in regard to frequency dispersion and surface roughness. © 1970 Elsevier Sequioa S.A., Lausanne.