Acid treatment of titania pastes to create scattering layers in dye-sensitized solar cells

Abstract

In dye-sensitized solar cells (DSC) scattering layers are used to increase the path length of light incident on the TiOfilm. This is typically achieved by the deposition of an additional TiOlayer on top of an existing transparent film and designed to trap light. In this work we show that a simple acid pretreatment can lead to the formation of a scattering skin on the surface of a single TiOfilm performing a similar function to a scattering layer without any additional depositions. This is important in increasing manufacturing throughput for DSCs as further TiOdepositions require additional materials and heat treatment. The pretreatment leads to self-assembly of a scattering layer of TiOwhich covers the surface on short-term immersion (30 min) and penetrates the bulk layer upon longer immersion. The method has been shown to increase the efficiency of the device by 20. © 2012 Trystan Watson et al.