On the Warburg Parameter of the Ag/AgI Electrode

The possible origins of frequent deviations from the calculated and experimentally obtained values of the Warburg parameter of the Ag/AgI electrode are discussed. Following the considerations of possible conditions for classical Warburg impedance to appear in solid AgI, it is suggested that the overall Warburg impedance of the Ag/AgI electrode could be considered as the sum of the Warburg impedances in series, one in the solid, and the other in the solution phase. In addition, the influence of diffusion controlled adsorption of I- ions in parallel with diffusion controlled ion-transfer on the experimentally obtained values of the Warburg parameter is discussed. A different theoretical approach to the analysis of the Warburg impedance of the Ag/AgI electrode is suggested, different from those formerly applied