Researchers at the
Organic solar cells have long relied on Indium Tin Oxide (ITO) coated glass as the transparent electrode, although this is largely due to the absence of a suitable alternative. ITO is a complex, unstable material with a high surface roughness and tendency to crack upon bending if supported on a plastic substrate. If that wasn’t bad enough one of its key components, indium, is in short supply making it relatively expensive to use.
An ultra-thin film of air-stable metal like gold would offer a viable alternative to ITO, but until now it has not proved possible to deposit a film thin enough to be transparent without being too fragile and electrically resistive to be useful.
Now research led by Dr Ross Hatton and Professor Tim Jones in the
Dr Hatton says “This new method of creating gold based transparent electrodes is potentially widely applicable for a variety of large area applications, particularly where stable, chemically well-defined, ultra-smooth platform electrodes are required, such as in organic optoelectronics and the emerging fields of nanoelectronics and nanophotonics”
The full research paper entitled Ultrathin Transparent Au Electrodes for Organic Photovoltaics Fabricated Using a Mixed Mono-Molecular Nucleation Layer is published in Advanced Functional Materials: http://dx.doi.org/10.1002/adfm.201002021.
The paper documents the team’s success in creating this simple, practical and effective method of depositing the films onto glass, and also reports how the optical properties can be fine tuned by perforating the film with tiny circular holes using something as simple as polystyrene balls. The University of Warwick research team has also had some early success in depositing ultra-thin gold films directly on plastic substrates, an important step towards realising the holy grail of truly flexible solar cells. This innovation is set to be exploited by Molecular Solar Ltd, a Warwick spinout company dedicated to commercialising the discoveries of its academic founders in the area of organic solar cells.
This work was supported by the European Regional Development Fund (ERDF) / Advantage West Midlands Science City SCRA AM2 project, the Engineering and Physical Sciences Research Council (EPSRC) and the Royal Academy of Engineering.
For further information please contact:
Dr Ross Hatton, Assistant Professor of Chemistry
Royal Academy of Engineering/EPSRC Research Fellow
Department of Chemistry, University of Warwick
Tel. +44(0)24761 50874
Peter Dunn, Head of Communications
Communications Office, University House,
University of Warwick, Coventry, CV4 8UW, United Kingdom
Tel: +44 (0)24 76 523708 Mobile/Cell: +44 (0)7767 655860
PR51 6th April 2011