METHOD FOR MEASURING POTENTIAL OF LIVE MAIN ELECTRODE OF ELECTROCHEMICAL CELL

摘要

FIELD: electrochemistry. SUBSTANCE: method involves interruption of electric current passed between main and auxiliary electrodes and metering of main electrode current potential; main-electrode potential Emeas is continuously measured relative to comparison electrode for time t, then potential value measured is used to calculated first derivative as function of main-electrode potential variation with time: ψ(t) = ΔEmeas/Δt,, where ψ(t) is first derivative as function of variation in current potential with time; ΔEmeas is current potential increment within time interval Δt; Δt is time interval; variations in current potential of main electrode between first and second extremes of first derivative ψ(t) after current interruption takes place due to resistive voltage drop across electrolyte; variations in main electrode current potential between first and second extremes of first derivative ψ(t) are due to discharge of double electric layer, and main electrode current potential E¿º¼ at third extremum point of first derivative ψ(t) corresponds to main electrode potential E; after that, current measured at interruption moment is recovered, and measurement of main electrode potential is stopped; current interruption time is chosen within time interval between 0.01 and 10 s and transient time of current interruption is set below discharge time of double electric layer of main electrode. EFFECT: improved measurement accuracy. 5 dwge