The talk will summarize our research and development activities of dye-sensitized solar cells (DSC), focusing on the development of characterisation techniques of complete DSC devices - what we call the 'tool-box'.

The scientific challenge of DSC is to handle the complex molecular interactions and the inherent multi-scaling properties, both in time and length. We have approached this scientific challenge by developing what we call 'tool'box' techniques. These techniques make it possible to extract information at the molecular level on complete DSC devices operating under normal working conditions. The methods provide information on for example energetics, charge transport and electron transfer processes. Some examples will be given at the meeting including Photoinduced Absorption Spectroscopy as a suitable method to study for example the quality of pore filling in case of solid hole conductors.

Some of our materials research will be presented. We have developed series of organic dye molecules with the general structure donor - conjugated linker - acceptor. Best efficiencies, above 7%, were obtained with polyene-diphenylaniline type dyes, using an iodide/triodide based redox electrolyte. The influences of substitutions of the donor group (a diphenylaniline moiety), the length of the conjugated linker chain and different acceptor/anchoring groups are presently being studied and will be discussed at the meeting.

The majority of studies in this field are based on the sensitization of a n-type semiconductor. However, DSCs in which the cathode is photoactive are also possible and the development of a photocathode can provide an entry to the preparation of a tandem solar cell, in which both electrodes are photoactive. Until now there have been few studies on the sensitization of p-type semiconductors. We will report on a new organic dye, designed for a p-type DSC, and its performance in a photovoltaic device based on NiO as the photocathode and a passive anode. The external quantum yield of this system has a maximum of about 18%, which is among the highest values recorded so far for p-type DSCs.