Molecular Engineering of Organic Chromophores for Dye Sensitized Solar Cell Applications
2008 (English)In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 130, 6259-6266 p.Article in journal (Refereed) Published
Novel unsymmetrical organic sensitizers comprising donor, electron-conducting, and anchoring groups were engineered at a molecular level and synthesized for sensitization of mesoscopic titanium dioxide injection solar cells. The unsymmetrical organic sensitizers 3-(5-(4-(diphenylamino)styryl)thiophen-2-yl)-2-cyanoacrylic acid (D5), 3-(5-bis(4-(diphenylamino)styryl)thiophen-2-yl)-2-cyanoacrylic acid (D7), 5-(4-(bis(4-methoxyphenylamino)styryl)thiophen-2-yl)-2-cyanoacrylic acid (D9), and 3-(5-bis(4,4'-dimethoxydiphenylamino)styryl)thiophen-2-yl)-2-cyanoacrylic acid (D11) anchored onto TiO2 and were tested in dye-sensitized solar cell with a volatile electrolyte. The monochromatic incident photon-to-current conversion efficiency of these sensitizers is above 80%, and D11-sensitized solar cells yield a short-circuit photocurrent density of 13.90 +/- 0.2 mA/cm(2), an open-circuit voltage of 740 +/- 10 mV, and a fill factor of 0.70 +/- 0.02, corresponding to an overall conversion efficiency of 7.20% under standard AM 1.5 sun light. Detailed investigations of these sensitizers reveal that the long electron lifetime is responsible for differences in observed open-circuit potential of the cell. As an alternative to liquid electrolyte cells, a solid-state organic hole transporter is used in combination with the D9 sensitizer, which exhibited an efficiency of 3.25%. Density functional theory/time-dependent density functional theory calculations have been employed to gain insight into the electronic structure and excited states of the investigated species.
Place, publisher, year, edition, pages
ACS , 2008. Vol. 130, 6259-6266 p.
nanocrystalline tio2, electron-injection, recombination, semiconductor, chromophores, conductor, energies, dynamics, acceptor, model
IdentifiersURN: urn:nbn:se:kth:diva-10534DOI: 10.1021/ja800066yISI: 000255620200032ScopusID: 2-s2.0-43249114905OAI: oai:DiVA.org:kth-10534DiVA: diva2:218892
QC 201007162009-05-252009-05-252012-02-23Bibliographically approved