Chemisorption of a thiol-functionalized ruthenium dye on zinc oxide nanoparticles: Implications for dye-sensitized solar cells

Authors

Jagdeep Singh, University of Massachusetts - Lowell
Jisun Im, University of Massachusetts - Lowell
James E. Whitten, University of Massachusetts - LowellFollow
Jason W. Soares, US Army Natick Soldier Research
Diane M. Steeves, US Army Natick Soldier ResearchFollow

Date of this Version

2010

Comments

Published in Chemical Physics Letters, 497, (2010), 196–199

Abstract

ZnO is an alternative to TiO₂-based dye-sensitized solar cells (DSSCs). Adsorption of cis-rutheniumbis [2,2'-bipyridine]-bis[4-thiopyridine] onto ZnO nanorods has been studied using X-ray and ultraviolet photoelectron spectroscopies (XPS and UPS). XPS indicates chemisorption with a surface density of ca. 1 × 10¹⁵ molecules/cm², confirming the possibility of using thiol-terminated dyes for ZnO-based DSSC devices. The energy level diagram, based on UPS and absorbance spectroscopy, indicates that the LUMO of this dye is lower in energy than the ZnO conduction band edge, providing minimal enthalpic driving force for photovoltaic electron injection. However, optimization of thiol-functionalized Ru dyes could result in competitive ZnO-based DSSCs.