Sensitization to Near-infrared Light and Improvement of Titanium Dioxide Compact Layers for Efficient Dye-sensitized Solar Cells

Author

• Curtiss S. Kovash

Document Type

Dissertation - University Access Only

Award Date

2012

Degree Name

Doctor of Philosophy (PhD)

Department / School

Chemistry and Biochemistry

Abstract

Methods of improving the solar energy conversion efficiency of dye-sensitized solar cells (DSSCs) were developed. In this project, two different aspects of the DSSCs were improved upon: the contact between the titanium dioxide photoelectrode and the transparent conductive oxide support , and the ability of DSSCs to convert near-infrared (NIR) solar energy into electricity. These were accomplished by altering the composition of the compact layer and the creation of novel NIR absorbing dyes. An improved method for producing nanometer scale titanium dioxide particles was developed. This resulted in the production of titanium dioxide particles with 4 .5 nm diameter, which were then used as a compact layer in DSSCs. The packing of these small particles resulted in improved electrical contact between the titanium dioxide photoelectrode and the transparent conductive oxide support, thus reducing the series resistance in the devices . Additionally , the compact layer prevented the electrolyte from coming in contact with the transparent conductive oxide layer, which in tum decreased the shunt resistance in these devices. The solar energy conversion efficiency of devices prepared with these compact layers was improved by 25.3% relative to devices produced with no compact layer. Three novel , near-infrared absorbing heteroleptic nickel complexes were synthesized . The purpose of these complexes was to absorb near-infrared light, which titanium dioxide and most sensitizers cannot do efficiently, and convert that light into electricity. When used in a DSSC with an electrolyte capable of regenerating the sensitizer, the complex ( carboxycyclopentadienyl)( 1,3-dithiole-2-thione-4,5-diselenolato) nickel(III) (KL-3) was able to sensitize the devices to near-infrared light.

Library of Congress Subject Headings

Dye-sensitized solar cells
Titanium dioxide
Near infrared spectroscopy 

Publisher

South Dakota State University

Recommended Citation

Kovash, Curtiss S., "Sensitization to Near-infrared Light and Improvement of Titanium Dioxide Compact Layers for Efficient Dye-sensitized Solar Cells" (2012). Electronic Theses and Dissertations. 1947.
https://openprairie.sdstate.edu/etd2/1947