Upright-standing SnO2 nanowalls: Fabrication, dual-photosensitization and photovoltaic properties

Abstract

We report on fabrication of upright-standing SnO2 nanowalls aligned on FTO substrates by a facile wet chemical method at low temperature. These nanowalls are dual-photosensitized with CdS quantum dots and Z907 dye molecules in order to construct panchromatic dye-sensitized solar cells. We demonstrate that thin CdS quantum dot layer not only acts as a blocking layer preventing recombination of charge carriers, but also contributes as a light absorber. A 158% improvement in power conversion efficiency is observed, which is attributed to improved light absorption, reduced recombination and improved charge collection in presence of CdS quantum dot interlayer. (C) 2012 Elsevier B. V. All rights reserved.