Electrolytes for dye-sensitized solar cells based on interhalogen ionic salts and liquids
Mikhail Gorlov1, Henrik Pettersson, Anders Hagfeldt
1Center of Molecular Devices, Department of Chemistry, The Royal Institute of Technology, Teknikringen 30, S-100 44 Stockholm, Sweden.
Inorganic Chemistry
|April 10, 2007
Summary
New interhalogen ionic liquids were synthesized and utilized as electrolytes in dye-sensitized solar cells, achieving efficiencies up to 6.4%. These novel electrolytes demonstrate promising stability for solar energy applications.
Area of Science:
- Materials Science
- Electrochemistry
- Solid-State Chemistry
Background:
- Ionic liquids offer tunable properties for electrochemical applications.
- Interhalogen compounds present unique chemical characteristics.
- Dye-sensitized solar cells (DSSCs) require efficient and stable electrolytes.
Purpose of the Study:
- To synthesize and characterize novel interhalogen ionic liquids.
- To investigate the application of these ionic liquids as electrolyte components in dye-sensitized solar cells.
- To evaluate the performance and stability of DSSCs utilizing these new electrolytes.
Main Methods:
- Synthesis of interhalogen ionic liquids with general formula [K+]XY2-.
- Characterization using NMR, IR, Raman, and mass spectroscopy.
- Fabrication and testing of encapsulated monolithic dye-sensitized solar cells.
Main Results:
- Successful preparation and characterization of interhalogen ionic liquids, including structural analysis of the linear Br-I-Br anion.
- Observation of anion equilibria in solution.
- Achieved light-to-electricity conversion efficiencies of up to 6.4% (gamma-butyrolactone), 5.0% (glutaronitrile), and 2.4% (native ionic liquids).
- Demonstrated stability with only 9-14% performance loss after 1000 hours of illumination.
Conclusions:
- Interhalogen ionic liquids are viable electrolyte components for dye-sensitized solar cells.
- The choice of solvent significantly impacts cell efficiency.
- These novel electrolytes show potential for stable and efficient solar energy conversion.
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