Aim of the work is to design modified Dye Sensitized Solar Cells (DSCs) with increased solar energy-to-current conversion efficiency, by exploring innovative modification of the original DSC structure devised by M. Graetzel at the beginning of the ‘90s.
The strategy followed to obtain this goal is to propose modifications regarding both the oxide substrate and the sensitizing layer of the cell aiming at increasing electron collection and transport while decreasing the recombination processes. The polycrystalline TiO2 layer will be substituted with (i) an ordered array of ZnO nanowires, (ii) a nano-network composed of ZnO nanowires covered with polycrystalline TiO2 (core-shell nanowires) or (iii) a nano-network composed by polycrystalline TiO2 and carbon nanotubes (CNTs).
The structural and electrical properties of these films will be modulated to achieve better collection and transport of electrons. In order to increase the power conversion, enhanced absorption schemes will also be pursued; in particular, two systems will be explored: i) plasmonics nanoparticles (NPs), ii) 3D photonic crystals.
Moreover, a step towards the production of cheap cells on flexible DSC substrates by means of the inkjet printing technology will be done, defining the optimal composition of inks containing ZnO nanowires and TiO2 nanoparticles and/or CNTs, as well as inks containing the sensitizers and jettable electrolyte gels.