Prof. Bruce Parkinson will present a colloquium lecture in Chemistry on 6th March 2020 from 3:15 pm on “Sensitization of Oxide Single Crystals with Quantum Confined Semiconductors”. Bruce Parkinson is currently professor of Chemistry and Energy Resources at University of Wyoming. He is a well-accomplishes materials chemist with special emphasis on studying surface phenomenon and electrochemistry. The abstract of his colloquium presentation is as follows:

Sensitization of Oxide Single Crystals with Quantum Confined Semiconductors
We study the fundamentals of electron injection by molecules, quantum dots, quantum confined nanoplatelets and semiconducting nanotubes into large bandgap metal oxide semiconductors and gallium phosphide. We have been testing a theoretical model that predicts that the photocurrent yields and photocurrent-voltage behavior are controlled by the doping density that then determines the field gradient of the Schottky barrier at the electrode/electrolyte interface. The model was shown to be applicable to sensitization by both thiacyanine and ruthenium based sensitizing dyes with the difference of the behavior between the two classes of dyes being attributed to the different distance of the photogenerated hole on the dye from the injected electron that influences the rate of the back reaction. We have extended these studies to monolayers of adsorbed CdSe quantum dots (QDs) of various sizes on well- characterized TiO 2 single crystals with varying doping densities. We are also building on our previous work where we were able to observe sensitized photocurrent quantum yields >1 from multiple exciton generation and collection from PbS quantum dots adsorbed on single crystal anatase electrodes and are working on preparation of InSb QDs that may be capable of producing 3 excitons per high energy photon.

Bruce Parkinson received his BS in chemistry at Iowa State University in 1972 and his PhD from Caltech in 1977 under the guidance of Professor Fred Anson. After a year of post-doctoral studies at Bell Laboratories with Adam Heller he was a staff scientist at the Ames Laboratory. He then became a senior scientist at the Solar Energy Research Institute (now known as the National Renewable Energy Laboratory) in Golden, Colorado. He then joined the Central Research and Development Department of the DuPont Company in 1985. In 1991 he became Professor of Chemistry at Colorado State University until his recent departure to join the Department of Chemistry and the School of Energy Resources at the University of Wyoming. His current research covers a wide range of areas including materials chemistry, UHV surface chemistry and photoelectrochemical energy conversion.