Condensed Matter Seminar (News&Views series): Thursday 22 April 2021 at 4:00 pm

[CMSP Seminars Secretariat]

Virtual - Zoom Meeting

CMSP News & Views Seminar
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/
/The News & Views Seminars are meant to address our section as a whole, 
and therefore include an extensive pedagogical introduction to the 
topic, and present the main physical ideas of the research in a way 
understandable by everybody in the section. The goal is to bridge 
distances among different subgroups of our diverse CMSP section. //The 
diversity in our section makes it a unique place for crossing bridges 
among different topics, and for cross-fertilization among seemingly 
distant fields. /
** * * Thursday 22 April 2021 at 4:00 p.m.*** * **

Speaker: *Thomas W. Hamann*   (Michigan State University, Department of 
Chemistry)

Title: *Semiconductor and Catalyst Systems for Solar Water Oxidation*
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Register in advance at:
https://zoom.us/meeting/register/tJAvc-GoqTgvGNQ7vJF7L5DJjsxHLYJzRJ0W
and you will receive a confirmation email containing information about 
joining the Zoom seminar room.



Abstract:

This seminar will describe some of our efforts to understand and control 
the processes determining the efficiency of energy conversion systems. 
Specifically, the behavior of metal oxide thin films for 
photoelectrochemical (PEC) water oxidation will be discussed. Under PEC 
water oxidation conditions, many metal oxides have been shown to 
accumulate holes in surface states which can recombine with conduction 
band electrons and thus limit the performance. The nature of such 
surface states will be elucidated and its role in controlling water 
oxidation discussed. Surface state recombination can generally be 
mitigated through introduction of electrocatalysts on metal oxide 
semiconductor surfaces which generally leads to improved performance. We 
have found that some semiconductor/catalyst combinations result in 
similar or worse performance compared to the bare electrode, however. 
Through rigorous comparison of cyclic voltammetry, current transient and 
electrochemical impedance spectroscopy (EIS), intensity modulated 
photocurrent spectroscopy (IMPS), and dual-working electrode experiments 
measurements, we have been able to gain significant insight into the 
role of the catalyst and the electron-transfer reactions at the 
interface on the performance of PEC water oxidation.


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CMSP, Condensed Matter & Statistical Physics Section
http://www.ictp.it/research/cmsp.aspx

The Abdus Salam International Centre for Theoretical Physics
https://www.ictp.it/

    
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