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Updated: Jul 31, 2026
11:26
Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light
Published on: September 12, 2014
An alternative efficient redox couple for the dye-sensitized solar cell system
Hervé Nusbaumer1, Shaik M Zakeeruddin, Jacques-E Moser
1Laboratory for Photonics and Interfaces Institute of Molecular and Biological Chemistry Swiss Federal Institute of Technology, 1015 Lausanne, Switzerland. herve.nusbaumer@epfl.ch
Chemistry (Weinheim an Der Bergstrasse, Germany)
|August 14, 2003
Summary
New cobalt complexes show promise as redox mediators for dye-sensitized solar cells. The best performing mediator, [Co(dbbip)(2)](ClO(4))(2), achieved high efficiencies in converting light to electricity.
Area of Science:
- Materials Science
- Electrochemistry
- Renewable Energy
Background:
- Dye-sensitized solar cells (DSSCs) are a promising photovoltaic technology.
- Efficient redox mediators are crucial for DSSC performance.
- Cobalt complexes offer tunable redox properties for solar energy applications.
Purpose of the Study:
- To synthesize and evaluate novel cobalt complexes as redox mediators for DSSCs.
- To investigate the impact of ligand structure and counterions on photovoltaic performance.
- To identify optimal conditions for high-efficiency solar energy conversion.
Main Methods:
- Synthesis of new cobalt complexes with varying ligand structures and counterions.
- Fabrication and testing of DSSCs using synthesized cobalt complexes as redox mediators.
- Photovoltaic performance characterization, including incident photon-to-current conversion efficiency (IPCE) and power conversion efficiency (PCE).
Main Results:
- The cobalt complex [Co(dbbip)(2)](ClO(4))(2) demonstrated superior performance as a redox mediator.
- IPCE values reached up to 80% with the optimized cobalt complex.
- Power conversion efficiencies of 8% under 100 W m(-2) and over 4% under 1000 W m(-2) AM1.5 simulated sunlight were achieved.
- Optimized photoelectrode structure (nanoporous and light-scattering layers) and hydrophobic ruthenium dye sensitization were critical.
Conclusions:
- Cobalt complexes, particularly [Co(dbbip)(2)](ClO(4))(2), are effective redox mediators for DSSCs.
- Ligand design and counterion selection significantly influence photovoltaic performance.
- The developed DSSC system demonstrates potential for efficient solar energy conversion.
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