Extraction of Faradaic Signals from Flash Photocurrent Measurements--Benzophenone Photolysis.

摘要

The first paper in this series developed a theoretical model for characterizing the charging currents induced by changing faradaic currents measured under potentiostatic conditions. Of specific concern here are photoelectrochemical measurements, although the principles are generally applicable to chronoamperometry. This paper is concerned with experimental verification of the predicted relationships and demonstration of the direct applicability of the model to the correction of experimental data for more accurate determination of faradaic currents. Corrected and uncorrected data are given for the potentiostatic and potential-step cases, both in the form of current-time profiles and Cottrell plots. Effects of variation of the cell time constant are presented to further demonstrate the magnitude of the charging effect and consistency of the model. The flash photolysis instrumentation, including computerization, used to obtain the experimental data for this work is also described.