title: Introducing manganese complexes as redox mediators for dye-sensitized solar cells.
abstract: The abundance and low toxicity of manganese have led us to explore the application of manganese complexes as redox mediators for dye sensitized solar cells (DSCs), a promising solar energy conversion technology which mimics some of the key processes in photosynthesis during its operation. In this paper, we report the development of a DSC electrolyte based on the tris(acetylacetonato)manganese(iii)/(iv), [Mn(acac)3](0/1+), redox couple. PEDOT-coated FTO glass was used as a counter electrode instead of the conventionally used platinum. The influence of a number of device parameters on the DSC performance was studied, including the concentration of the reduced and oxidized mediator species, the concentration of specific additives (4-tert-butylpyridine, lithium tetrafluoroborate, and chenodeoxycholic acid) and the thickness of the TiO2 working electrode. These studies were carried out with a new donor-π-acceptor sensitizer K4. Maximum energy conversion efficiencies of 3.8% at simulated one Sun irradiation (AM 1.5 G; 1000 W m(-2)) with an open circuit voltage (VOC) of 765 mV, a short-circuit current (JSC) of 7.8 mA cm(-2) and a fill factor (FF) of 0.72 were obtained. Application of the commercially available MK2 and N719 sensitizers resulted in an energy conversion efficiency of 4.4% with a VOC of 733 mV and a JSC of 8.6 mA cm(-2) for MK2 and a VOC of 771 mV and a JSC of 7.9 mA cm(-2) for N719. Both dyes exhibit higher incident photon to current conversion efficiencies (IPCEs) than K4.
authors.affiliation: School of Chemistry, Monash University, Victoria 3800, Australia. leone.spiccia@monash.edu.
authors.forename: Ishanie Rangeeka
authors.initials: IR
authors.lastname: Perera
authors.forename: Akhil
authors.initials: A
authors.lastname: Gupta
authors.forename: Wanchun
authors.initials: W
authors.lastname: Xiang
authors.forename: Torben
authors.initials: T
authors.lastname: Daeneke
authors.forename: Udo
authors.initials: U
authors.lastname: Bach
authors.forename: Richard A
authors.initials: RA
authors.lastname: Evans
authors.forename: C André
authors.initials: CA
authors.lastname: Ohlin
authors.forename: Leone
authors.initials: L
authors.lastname: Spiccia
mesh_terms: D004396:Coloring Agents / Q000737:chemistry*; D011211:Electric Power Supplies; D008345:Manganese / Q000737:chemistry*; D010084:Oxidation-Reduction; D012993:Solar Energy
chemical_list: D004396:Coloring Agents; D008345:Manganese