Triphenylamine Groups Improve Blocking Behavior of Phenoxazine Dyes in Cobalt-Electrolyte-Based Dye-Sensitized Solar Cells
2014 (English)In: ChemPhysChem, ISSN 1439-4235, E-ISSN 1439-7641, Vol. 15, no 16, 3476-3483 p.Article in journal (Refereed) Published
Novel phenoxazine dyes are successfully introduced as sensitizers into dye-sensitized solar cells (DSCs) with cobalt-based electrolyte. In sensitizers with triphenylamine (TPA) groups recombination from electrons in the TiO2 conduction band to the cobalt(III) species is suppressed. The effect of the steric properties of the phenoxazine sensitizers on the overall device performance and on recombination and regeneration processes is compared. Optimized DSCs sensitized with IB2 having two TPA groups in combination with tris(2,2'-bipyridyl) cobalt( II/III) yield efficiencies of 6.3 %, similar to that of IB3, which is equipped with mutiple alkoxy groups. TH310 with only one TPA group gives lower efficiency and open circuit voltage, while IB1 without TPA groups performs even worse. These results demonstrate that both TPA groups on the IB2 are needed for an efficient blocking effect. These results reveal a possible new role for TPA units in DSC sensitizer design.
Place, publisher, year, edition, pages
2014. Vol. 15, no 16, 3476-3483 p.
blocking effect, cobalt redox mediator, dye-sensitized solar cells, phenoxazine dyes, triphenylamine
Physical Sciences Chemical Sciences
IdentifiersURN: urn:nbn:se:kth:diva-157024DOI: 10.1002/cphc.201402474ISI: 000344370900009PubMedID: 25123399OAI: oai:DiVA.org:kth-157024DiVA: diva2:768844
FunderSwedish Energy AgencySwedish Research CouncilStandUpKnut and Alice Wallenberg Foundation
QC 201412052014-12-052014-12-042014-12-05Bibliographically approved