Detailed mechanistic understanding of the optoelectronic features is a key factor in designing efficient semiconductor (photo)electrodes. In situ spectroelectrochemical methods and electrochemical impedance spectroscopy provides an opportunity to scrutinize the effect of trap states on the optical and electronic properties of semiconductors. Different metal oxides and halides were studied, and results gathered for TiO2, NiO and CuI will be presented in this talk. The absorption bands in the UV-visible spectrum and the Raman spectral features were directly influenced by the applied bias potential. These spectral changes correlate with the alterations observed in the electrical conductivity. Interestingly, the population/depopulation of the trap states, that are responsible for both the changes in the optical and electronic properties, occur in a different potential/energy regime. In the function of these results, we can optimize the properties of the given semiconductor to make it the most appropriate for different applications. The hole transporting behavior of p-type semiconductors is very important for solar cell research, however if there are a lot of defects inside the band gap which can trap the holes, we must know the conditions, which allow us to use the transporting layers efficiently. In the case of TiO2, hydrogen treatment causes a remarkable increase in the donor density by creating oxygen vacancies which behave as shallow electron donors. I will show how the presence of these states affects the (photo)catalytic activity and the photoelectrochemical performances of TiO2.

Effect of trap states in semiconductor electrodes on their optoelectronic and photoelectrochemical behavior

Macromolecular Chemistry: The Second Century

[Author Benefits](https://scimeetings.acs.org/?utm_source=pubs_content_marketing&utm_medium=website&utm_campaign=0320_MCF_NPI_Launch_Spring_Homepage&ref=pubs_content_marketing)

[How to use SciMeetings](https://storage.googleapis.com/dl.morressier.com/acs/SciMeetings-ACSSpring2020-HowToGuide_M3020-Final.pdf)

[Frequently Asked Questions](https://storage.googleapis.com/dl.morressier.com/acs/SciMtng_ACSNMSp2020_FAQ_M3120_Final.pdf)

ACS Spring 2020 National Meeting & Expo

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.