Ru(ii) sensitizers with a tridentate heterocyclic cyclometalate for dye-sensitized solar cells
Journal
Energy and Environmental Science
Journal Volume
5
Journal Issue
6
Pages
7549-7554
Date Issued
2012
Author(s)
Abstract
A new series of bis-tridentate, thiocyanate-free Ru(ii) complexes (TF-21-TF-24), containing the 2-azolyl-6-phenylpyridine cyclometalate, were synthesized. Upon switching from a pyrazolyl to a more electron deficient triazolyl moiety, the oxidation potentials were fine-tuned to readily accept electrons from the I-/I3- redox couple, so that the dye regeneration proceeds efficiently amid the device operation. This, together with high concentrations of 1,3-dimethylimidazolium iodide in the electrolyte which accelerates dye regeneration, attains a short-circuit photocurrent density as high as 18.09 mA cm-2 and an overall efficiency of 9.04%. The trifling decrease (3-6%) in efficiency after 1000 h of illumination at 60°C manifests the high device stability, due to the much suppressed solvent volatility in combination with the robust bis-tridentate structure involved in cyclometalating the 2-azolyl-6-phenylpyridine ancillary. © 2012 The Royal Society of Chemistry.
SDGs
Other Subjects
Synthesis (chemical); Device operations; Device stability; Dye regeneration; Dye-Sensitized solar cell; Electron-deficient; High concentration; Overall efficiency; Oxidation potentials; Pyrazolyl; Redox couple; Ru complexes; Short-circuit photocurrent; Solvent volatility; Ruthenium alloys; complexation; concentration (composition); dye; electrolyte; equipment; iodide; organometallic compound; oxidation; phenolic compound; photovoltaic system; ruthenium; solar power; solvent; volatile substance
Type
journal article