Resistência interna de células solares fotovoltaicas de Si e TiO2

Abstract

Interest in research concerning renewable energy sources has grown in recent decades. In this context the study of the physical processes important in the conversion of solar energy radiation via the photovoltaic effect has increasingly been studied theoretically and experimentally. In this thesis we take a thermodynamical approach to the solar energy conversion problem. Specifically, we discuss the photovoltaic effect in pn junctions found in Si solar cells as well as the photoelectrochemical effect at semiconductor-electrolyte interfaces in TiO2 dye sensitized solar cells. Next we discuss the theoretical limits for the conversion efficiency for Si and TiO2 cells. Given the importance of internal resistance for viable operation of photovoltaic solar cells, we investigate the internal resistance of both types of solar cells. Finally, we propose a new phenomenological model for the internal resistance of nanocrystalline TiO2 dye sensitized solar cells.