Influence of Interface Morphology onto the Photovoltaic Properties of Nanopatterned ZnO/Poly(3-hexylthiophene) Hybrid Solar Cells. An Impedance Spectroscopy Study

This paper focuses on the characterization of the ZnO/poly(3- hexylthiophene) (P3HT) interfaces in nanostructured hybrid solar cells, aiming to elucidate the relationship between thermal treatment, local morphology, and device performance. An equivalent impedimetric model for the device is proposed, allowing us to extract information about the ZnO/P3HT interface morphology and its impact on the photovoltaic properties by comparing devices with and without nanopatterning. It is found that the influence of thermal treatment on performance lies solely in the interface, resulting from a different interfacial morphology of P3HT depending on which crystal direction of ZnO is present. © 2011 American Chemical Society.