A&P Seminar - Stephen Maldonado

The Analytical and Physical Seminar Series presents: Stephen Maldonado

University of Michigan

Host: Hang Ren

Title: Decoding Semiconductor Voltammetry - Solving a Mystery that Started at UT Austin in 1975

Refreshments served at 3:15pm

Location: WEL 2.122

Driving electrochemistry with light at a semiconductor (photo)electrode has long been a potential motif for realizing artificial photosynthetic reactor. The heart of such systems is heterogeneous electron transfer between a semiconductor solid and molecular donor/acceptor. As advocated by Al Bard 50 years ago, voltammetry is the logical experiment to probe such systems since the data is explicitly a measure of the reaction rate for such reactions. However, interpreting such data quantitatively has remained elusive, despite decades of reported data available in the literature. Essentially, there has never been an explanation of how to do it. This talk presents a framework to understand and to analyze the voltammetric responses of semiconductor electrodes comprehensively. A discussion of the relevant principles necessary to understand will be conveyed first followed by an analysis of several sets of data that separately and collectively demonstrate a unified method to interpret this type of voltammetry.