Developing in-spectrometer photochemistry and integration of molecular imaging techniques: Probing photoinduced electronic structure variations in dye-sensitized TiO2 model system
EMSL Project ID
34502
Abstract
The aim of this project is to develop capabilities that will advance the fundamental understanding of charge transfer and photochemical behavior of organic molecular layers on surfaces as applicable to solar cells, sensors and contaminant reduction. This would be accomplished by using model film systems, applying existing and newly developed tools to characterize film structure and order at multiple dimensions and by measuring the impact of relevant parameters such as film structure, substrate preparation and chemistry on the electronic and photoinduced electronic variations. These results on the model system will provide critical insight into the fundamental aspects of the energy level alignments that govern electron-transfer dynamics from the organic dye to TiO2, but which are unavailable from current examination of dye-sensitized TiO2 particles used in solar cells. The structural characterization of the films will involve different degrees of spatial and molecular resolution involving XPS, TOF-SIMS, a new fluorescence capability added to the ToF-SIMS, and at the highest spatial resolution PEEM. Electronic structure and photoinduced electronic structure will be measured by UPS and XPS by adding an optical capability to the new scanning multiprobe surface analysis system. Therefore, this effort will further enhance the important instrumental capability on the scanning multiprobe surface analysis (Versa Probe) and ToF-SIMS instruments as well as provide new expertise in characterization and function of molecular film structures.
Project Details
Start Date
2009-04-02
End Date
2012-04-08
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Karakoti AS, SP Sanghavi, P Nachimuthu, P Yang, and S Thevuthasan. 2011. "Probing the size and environment induced phase transformation in CdSe quantum dots." The Journal of Physical Chemistry Letters 2(22):2925-2929. doi:10.1021/jz201243t
Reid DL, KR Kreitz, MA Stephens, J King, P Nachimuthu, EL Petersen, and S Seal. 2011. "Development of Highly Active Titania-Based Nanoparticles for Energetic Materials." PNNL-SA-80602, Pacific Northwest National Laboratory, Richland, WA. [Unpublished]