Surface Metallization of Polyimide as a Photoanode Substrate for Rear-Illuminated Dye-Sensitized Solar Cells

Abstract

Plastic film is promising as a photoanode substrate of dye-sensitized solar cell (DSSC) for flexible applications, while a low-temperature sintering process is generally adopted for the TiO2 mesoporous film due to unstable thermal property of general plastics. This study demonstrates that typical high-temperature TiO2 sintering can be adopted for preparing the photoanode when using a surface-metallized polyimide (PI) film. A Sn/Ni bi-layer is formed on a PI film via a chemical process as the conductive layer. The Sn/Ni-coated PI photoanode can withstand high-temperature TiO2 sintering at a peak temperature of 430°C for 30 min without significant visual deformation due to high thermal stability of PI and strength reinforcement caused by surface metallization. The DSSC employing the Sn/Ni-coated PI film as the photoanode substrate reaches an energy conversion efficiency of 3.44% under 1 sun rear-side illumination.