POTENTIAL PROGRAM INVARIANT REPRESENTATION OF VOLTAMMETRIC MEASUREMENT RESULTS OF REVERSIBLE REDOX COUPLES

The use of a transformation is proposed by which the results of voltam metric measurements based on diffusion of reversible redox couples to an electrode of any geometry can be presented in the form of a standar dized function T. To characterize the time dependence of the diffusion we define the function G(s) by writing the Cottrell response of the s pecies i in the form (I) over bar(i,Cottrell)(s) = +/- K(i)c(i) G(s)/ s where K-i is a constant, c(i) the bulk concentration of the diffusi ng species, s the Laplace variable; then we show that: (a) any voltamm etric curve ((I) over bar(s)) measured in the same system can be trans formed to potential program invariant form by computing the function T = L-1{(I) over bar(s)/G(s)}; (b) the diffusional admittance of the sa me system is expressed by Y(s) = G(s)dT/dE; (c) one can perform the tr ansformation yielding the potential program invariant form by passing the I(t) function through a numeric filter having 1/G(s) transfer char acteristics.