CHEMICAL DIFFUSION-COEFFICIENTS OF THE LOW-TEMPERATURE PHASES OF CUXSE-INVESTIGATION AND CUXS-INVESTIGATION WITH POINT ELECTRODES

Chemical diffusion coefficients of mixed conducting low temperature phases of copper selenide and copper sulfide between 20 degree C and 80 degree C have been measured by a method which makes use of inert point electrodes. Earlier results on chalcocite (Cu//2S) were reproduced and extended. The electrochemical cell consisted of the phase sequence Pt/Cu//xY(Y equals S, Se)/Pt-point electrode. Chemical diffusion coefficients were evaluated from the time dependence of the ohmic resistance after an instant change of voltage or current.