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RESEARCH PRODUCT
The origin of slow electron recombination processes in dye-sensitized solar cells with alumina barrier coatings
Francisco Fabregat-santiagoGermà Garcia-belmonteJames R. DurrantSaif A. HaqueJorge García-cañadasEmilio PalomaresJuan BisquertJohn N. Cliffordsubject
Solar cellsCharge injectionPassivationAbsorption spectroscopyIon recombinationThin filmsAluminaAnalytical chemistryGeneral Physics and AstronomyPhotochemistryTime resolved spectraTitanium compounds ; Alumina ; Nanostructured materials ; Semiconductor materials ; Thin films ; Solar cells ; Ion recombination ; Dyes ; Charge exchange ; Charge transfer states ; Charge injection ; Electrochemical impedance spectroscopy ; Time resolved spectraSemiconductor materials:FÍSICA [UNESCO]Ultrafast laser spectroscopyCharge exchangeThin filmSpectroscopyDyesQCChemistryUNESCO::FÍSICANanostructured materialsAcceptorDielectric spectroscopyDye-sensitized solar cellTACharge transfer statesTitanium compoundsElectrochemical impedance spectroscopydescription
We investigate the effect of a thin alumina coating of nanocrystalline TiO2 films on recombination dynamics of dye-sensitized solar cells. Both coated and uncoated cells were measured by a combination of techniques: transient absorption spectroscopy, electrochemical impedance spectroscopy, and open-circuit voltage decay. It is found that the alumina barrier reduces the recombination of photoinjected electrons to both dye cations and the oxidized redox couple. It is proposed that this observed retardation can be attributed primarily to two effects: almost complete passivation of surface trap states in TiO2 that are able to inject electrons to acceptor species, and slowing down by a factor of 3–4 the rate of interfacial charge transfer from conduction-band states. emilio.palomares@uv.es
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2004-12-01 |