Imaging the photovoltaic response of PbS-sensitized porous titania

Abstract

We report the photovoltaic response of solid-state devices based on porous TiO 2 photosensitized with PbS nanocrystals. A photovoltaic response in the visible and near infrared wavelength range is obtained by exploiting the Schottky junction that forms at the interface between the PbS/TiO 2 film and a metallic contact. Spatial images of the photoluminescence and of the short circuit photocurrent signal reveal a non-homogeneous response, which we explain in terms of the electron transfer dynamics at the PbS/TiO 2 interface and the morphological properties of TiO 2. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.