Kenneth W. Hanck Analytical Chemistry
Professor
B.S., 1964, Illinois State University
M.S., 1967, University of Illinois
Ph.D., 1969, University of Illinois
Senior Fulbright Scholar, 1980

Current Research Interests

AC Voltammetry. Despite their high sensitivity, ac voltammetric techniques are not used as often as other electroanalytical techniques. Fundamental ac voltammetry (current measured at the same frequency as the applied voltage) has been applied for analysis and for the kinetic characterization of electrochemical reactions, but the use of the second harmonic ac voltammetry (current measured at twice the frequency of the applied voltage) is relatively rare.

Two features which make the use of second harmonic ac voltammetry attractive are the absence of charging current and the higher sensitivity to the kinetic status of electrochemical reaction. There are several reasons for the under-utilization of second harmonic ac voltammetry: complex mathematical expressions which relate current to fundamental electrochemical parameters, the lack of a convenient algorithm for extracting kinetic parameters from experimental voltammograms, a high sensitivity to the presence of uncompensated resistance and the lack of inexpensive, commercially available instrumentation. We have recently developed a computer based instrument and data analysis technique based on the second harmonic phase angle, which has provided excellent data when applied to model systems. The dependence of the second harmonic phase angle on kinetic parameters is well suited for the use of computer based algorithms to extract electrochemical kinetic parameters.

Selected Recent Publications

A Novel Approach to Digital AC Voltammetry, Senaratne, C; and Hanck, K.W., Chem. Instrumentation, 1992 (in press).

Use of AC Second Harmonic Phase Angle Voltammograms to Measure Heterogeneous Kinetic Parameters, Senaratne, C; and Hanck, K.W., J. ElectroanaL Chem., 1992 (in press),