Abstract

One of the challenging aspects in designing and developing novel functional materials is to incorporate the desired optical and electrical properties maintaining their film-forming and thermal characteristics which make them suitable for thin film device applications. An important criterion for most of the applications in the field of energy research such as photovoltaics, batteries, fuel cells etc. is that these materials should have well-defined nanostructured morphology in thin films in order to be capable of fulfilling the complex functions of charge carrier/ ion transport in confined channels/geometries without adversely affecting the other complimentary functions. This morphological control on a nanoscopic level controls the interface between the functional domains as well as the long term stability of such devices. We have demonstrated the chain of control on all length scales from molecular to mesoscopic to macroscopic using the self-assembly principle of a fully functionalised block polymer for photovoltaic applications as represented in fig 11-4.

This contribution covers the synthesis of some novel semiconductor block copolymers carrying poly(3-hexylthiophene) segments and others which allow the incorporation of semiconductor quantum dots or nanocrystals (e.g. CdSeTe) to get organic as well as hybrid systems for solar cell applications. The characterisation of these materials in thin films and their application in devices will be presented. In the field of solid-state dye sensitized solar cells, we have developed a series of high extinction donor antenna dyes capable of retarding recombination via a secondary electron donation from the donor antenna group to the dye centre. The chemistry and application of these dyes in solar cells will also be presented5,6. References: 1. S. M. Lindner, M. Thelakkat, Macromolecules 37, 8832 (2004). 2. S. M. Lindner, S. Hüttner, A. Chiche, M. Thelakkat, G. Krausch Angew. Chem. Int. Ed 45, 3364 (2006). 3. S. M. Lindner, N. Kaufmann, M. Thelakkat Organic Electronics 8, 69-75 (2007). 4. M. Sommer, S.M. Lindner, M. Thelakkat, Adv. Fun. Mat. 17, 1493-1500 (2007). 5. C. S. Karthikeyan, M. Thelakkat, Inorganica Chimica Acta 361 635–655 (2008). 6. C. S. Karthikeyan, H. Wietasch, M. Thelakkat, Adv. Mater. 19, 1091-1095 (2007).