Transparent nanocomposite electrodes based on thin films of mesoporous oxides with anchored electroactive sites

• Applicant: Professor Dr. Michael Wark
• Subject Area: Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry
• Term: from 2004 to 2007
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5443203

The project is aming at the development and electrochemical characterization of new transparent nanocomposite electrodes based on ordered mesoporous thin films of nonconductive SiO2 and conductive indium tin oxide (ITO) with embedded electroactive moieties (model redox systems, phthalocyanine and nitrospiropyrane dyes). A homogenous distribution of the guests will be enabled by a new stepwise grafting procedure developed by us in which the molecules are tightly anchored by covalent or ionic bonding. The open structure of the mesopourous matrix will ensure accessibility of the inner volume and enhanced diffusion of charge-balancing ions, whereas the tight anchoring of the active sites will prevent their leaching. The aim of the electrochemical characterization will be investigation and modeling of the charge propagation in these host-guest systems. The use of transparent thin films will allow the combination of electrochemical and spectroscopic measurements, providing additional information about charge propagation within the mesoporous structure and host-guest interactions. The application potential of the films in optoelectrochemical devices will thus be explored. The new mesoporous ITO matrix will open a way to a novel class of nanocomposite electrodes free of restrictions in conductivity.

• DFG Programme: Research Grants
• International Connection: Czech Republic
• Participating Persons: Dr. Torsten Oekermann; Dr. Jiri Rathousky