Low‐temperature fabrication of flexible TiO₂ electrode for dye‐sensitized solar cells

Abstract A novel method for preparing flexible porous titania electrode from commercial TiO₂ particles at low temperature for dye‐sensitized solar cells (DSSCs) was introduced. In this method, hydroxypropyl methyl cellulose (HPMC) as an additive was added to form a good‐quality TiO₂/HPMC film on indium‐tin‐oxide‐coated polyethylene naphthalate flexible substrate (PEN/ITO). The additive was subsequently decomposed via the TiO₂ photocatalytic degradation process under 365 nm UV‐light illumination at room temperature to form flexible multiporous TiO₂ electrode film. Electrochemistry impedance spectroscopy (EIS) analysis indicated that the resistance of TiO₂ film markedly decreased, and photocurrent–voltage curves showed that the photocurrent dramatically increased when the additive (HPMC) was removed from the flexible titania electrode film. The photocurrent conversion efficiency was estimated at 3.25% under 100 mW/cm² illuminations using this flexible film as the DSSC photoanode. magnified image Photocurrent versus voltages of the as‐prepared flexible DSSCs under AM 1.5 at 100 mW/cm² illumination: photoanode made from HPMC‐free TiO₂ paste (□) and photoanodes made from HPMC/TiO₂ paste with UV‐light illumination from 0 to 10 h.