381948 Reducing Electron Recombination in Dye Sensitized Solar Cells: A Comparative Study

Monday, November 17, 2014
Galleria Exhibit Hall (Hilton Atlanta)
Luping Li, Chemical Engineering, University of Florida, Gainesville, FL, Shikai Chen, University of Florida, Gainesville, FL, Cheng Xu, Chemical Engineering, University of Florida at Gainesville, Gainesville, FL, Yang Zhao, Chemical engineering, University of Florida at Gainesville, Gainesville, FL and Kirk J. Ziegler, Department of Chemical Engineering, University of Florida, Gainesville, FL

Establishing a compact barrier layer on the interfaces of photoanode is an effective approach to reduce the electron recombination in dye sensitized solar cells (DSSCs). However, electron recombination on transparent conductive oxide (TCO) and on TiO2 has not been compared to identify the dominant recombination process. In this work, by depositing HfO2 as barrier layers via atomic layer deposition (ALD) on tin-doped indium oxide (ITO) and TiO2, the recombination processes on the two interfaces are compared. 2 cycles of ALD deposition on ITO and TiO2 lead to their respective highest efficiency of 7.10% and 7.25%, corresponding to an enhancement of 10% and 10.4%, respectively. With more than 2 ALD cycles, the barrier layers showed blocking effect regardless of the location of deposition, resulting in decrease of efficiencies. Fill factor (FF) was seen to change with shunt resistance (Rsh) and series resistance (Rse), which in turn depend on the location of barrier layers. Depositing barrier layer on ITO did not impact Rsh and Rse, leaving FF unchanged. Depositing barrier layer on TiO2 leads to decrease of Rsh and increase of Rse, which ultimately reduced FF.

Extended Abstract: File Not Uploaded