Dye Sensitized Solar Cells With Nanostructured TiOFilms

Sunlight provides the energy for almost all life on Earth. Organic Solar Cells hold promise as an economical means of harvesting solar energy due to their ease of production and processing. In an Organic Solar Cells device, semiconducting polymers or small Organic molecules are used to accomplish the functions of collecting solar photons, converting the photons to electrical charges, and transporting the charges to an external circuit as a useable current. Organic Electronics deals with the conductive polymers, It is called "Organic" because the molecules in the Polymer are Carbon-based, like the molecules of living things. The advantage of polymeric photovoltaic cells when compared to electro-chemical cells is predominantly the absence of a liquid electrolyte, which generates problems with sealing against air, but also the prospect of even cheaper production using large area devices and the use of flexible substrates. Furthermore, their production is comparatively cheap as the organic materials are processable from solution and therefore no semiconductor technology in the production process is required. Dye-sensitized solar cells (DSSC) are studied with great interest because they constitute a low-cost alternative to conventional silicon photovoltaic cells. A major component of DSSCs is nanocrystalline TIO, deposited as a thin film on conductive glass electrodes. 'PhD Scholar, Anna University, Coimbatore. (Lecturer in Electronics, Govt. Polytechnic College, Palakkad) Professor, Sri Ramakrishna Engineering College, Coimbatore So far, these films are usually sintered at relatively high temperature, te. 400°C. However, there is a considerable effort being made recently to obtain TiO, films on flexible (plastic, organic) electrodes since this will increase the range of DSSC applications. Therefore, it is necessary to develop procedures of low-temperature TIO, deposition so as to protect the plastic substrate. In the present work, a simple and benign procedure of making low temperature TiO, films is described. According to this procedure commercially available TIO,-P25 was placed in the form of thick completely uniform films on ITO-PET (plastic) or F:SnO, (FTO) conductive glasses. Film nanostructure was characterized by microscopy techniques and nanoparticle crystallinity by X-ray analysis. The films were mechanically stable without any cracks. The overall efficiency of a quasi-solid state DSSC employing a nanocomposite organic-inorganic material as a solid gel electrolyte and TiO, film prepared in room temperature was measured and it was found that n-5.3% for the cell made with TCO glass and 3.2% for ITO-PET plastic substrate, Besides, the method that obtains DSSC in room temperature we employed similar nanostructured films prepared with sol-gel method calcinated at high- temperature for reasons of comparison. Quasi-Solid State Dye-sensitized Solar Cell employing the same nanocomposite organic-inorganic material as a solid gel electrolyte and a nanostrustured TiO, film prepared in high temperature using sol-gel syntheses result an overall efficiency exceeding 6% and they were compared with those obtained in room temperature.