A supercooled imidazolium iodide ionic liquid as a low-viscosity electrolyte for dye-sensitized solar cells.
A series of allyl-functionalized imidazolium salts are reported, including 1-allyl-3-ethylimidazolium iodide and 1-allyl-3-propylimidazolium iodide, which have melting points close to room temperature and show typical properties of supercooled fluids if heated above their melting points. Their viscosities in the liquid state are considerably lower than the benchmark ionic liquid used in solar cells, viz., 1-propyl-3-methylimidazolium iodide. Electrolytes containing these new liquids provide excellent efficiencies and good stability in dye-sensitized solar cells when subjected to an accelerated-light soaking test at 60 degrees C. The structures of three of the new salts have been established in the solid state by single-crystal X-ray analysis.
Fei
Zhaofu
Z
Institute of Chemical Sciences and Engineering and Laboratory for Photonics and Interfaces, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH 1015 Lausanne, Switzerland.
Kuang
Daibin
D
Zhao
Dongbin
D
Klein
Cedric
C
Ang
Wee Han
WH
Zakeeruddin
Shaik M
SM
Grätzel
Michael
M
Dyson
Paul J
PJ