Determination of the light-induced degradation rate of the solar cell sensitizer N719 on TiO2 nanocrystalline particles
2005 (English)In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 109, no 47, 22413-22419 p.Article in journal (Refereed) Published
The oxidative degradation rate, k(deg), of the solar cell dye (Bu4N+)(2)[Ru(dcbpyH)(2)(NCS)(2)](2-), referred to as N719 or [RuL2(NCS)(2)], was obtained by applying a simple model system. Colloidal solutions of N719-dyed TiO2 particles in acetonitrile were irradiated with 532-nm monochromatic light, and the sum of the quantum yields for the oxidative degradation products [RuL2(CN)(2)], [RuL2(NCS)(CN)(2)], and [RuL2(NCS)(ACN)], Phi(deg) was obtained at eight different light intensities in the range of 0.1-16.30 mW/cm(2) by LC-UV-MS. The Phi(deg) values decreased from 3.3 x 10(-3) to 2.0 x 10(-4) in the applied intensity range. By using the relation k(deg) = Phi(deg)k(back) and back electron-transfer reaction rates, k(back), obtained with photoinduced absorption spectroscopy, it was possible to calculate an average value for the oxidative degradation rate of N719 dye attached to TiO2 particles, k(deg) = 4.0 x 10(-2) s(-1). The stability of N719 dye during solar cell operation was discussed based on this number, and on values of the electron-transfer rate between [(RuL2)-L-(III)(NCS)(2)] and iodide ion that are available in the literature.
Place, publisher, year, edition, pages
2005. Vol. 109, no 47, 22413-22419 p.
titanium-dioxide films, osmium polypyridyl complexes, electron-transfer, transient absorption, dye sensitization, colloidal tio2, oxidation, ruthenium, iodide, spectroscopy
IdentifiersURN: urn:nbn:se:kth:diva-15225DOI: 10.1021/jp052792vISI: 000233684500048ScopusID: 2-s2.0-29144508878OAI: oai:DiVA.org:kth-15225DiVA: diva2:333266
QC 201005252010-08-052010-08-05Bibliographically approved