Probing the Charge Transfer Mechanism in Pentamethine Cyanine Dyes
George Fish a, Jacques-E Moser a
a Ecole Polytechnique Federale de Lausanne (EPFL), Switzerland, Lausanne, Switzerland
Proceedings of International Conference on Hybrid and Organic Photovoltaics (HOPV19)
Roma, Italy, 2019 May 12th - 15th
Organizers: Prashant Kamat, Filippo De Angelis and Aldo Di Carlo
Poster, George Fish, 228
Publication date: 11th February 2019

Cyanine dyes were originally developed for use as sensitisors in the photographic industry, but have more recently been exploited as materials for use in organic solar cells [1]. This is as a result of their beneficial properties such as their tuneable absorption wavelength and high extinction coefficients, the latter of which allows for the active layer of the device to be very thin (20 nm). [2]

Typically, cyanine dyes have been used alongside a fullerene-based acceptor, such as C60, in a bilayer heterojunction configuration. However, recent studies have shown that high bulk photoconductivity can be seen in pristine pentamethine cyanine (Cy5) dye films without the presence of a Donor/Acceptor interface. [3]

Here, femtosecond transient absorption spectroscopy has been employed alongside other techniques in order to investigate the photophysics of such Cy5 systems, and to begin to rationalise the charge transfer mechanism of these films which result in the reduced Langevin recombination, and therefore long carrier lifetime, that has been reported in these pristine Cy5 films. [3]

© Fundació Scito
We use our own and third party cookies for analysing and measuring usage of our website to improve our services. If you continue browsing, we consider accepting its use. You can check our Cookies Policy in which you will also find how to configure your web browser for the use of cookies. More info