Nanotecnologie per catturare la luce

Solar photovoltaic technology is based on the direct conversion of solar radiation power into electrical power by means of solar cells. Photovoltaics can in principle play a major role in the search for alternative energy sources, even though it is still not competitive with respect to traditional sources, e.g. based on fossil fuels. One of the most important challenges of current scientific research in this field relates to the development of new solar cell materials or new cell architectures, possibly leading to an improvement of the cell power conversion efficiency or to the parallel reduction of the energy production cost; nanotechnology plays a leading role in this framework. In this paper selected examples will be presented, which show the possible contribution of nanoscience and nanotechnology to the study and optimization of nanostructured materials for better future generation solar cells. After an introductory part presenting the different types of solar cells and highlighting the role of nanotechnology research in this field, two specific cases will be presented and discussed: the study of hierarchical titanium oxide nanostructures as photoanodes for novel dye-sensitized solar cells and the development of nanostructured transparent conducting oxides for designing multifunctional electrodes for organic or hybrid photovoltaic cells