Poly(3,4-Ethylenedioxythiophene) Inverse Opal Electrode Fabricated from Poly(3,4-Ethylenedioxythiophene):Poly(Styrene Sulfonate)-Filled Polystyrene Template for Dye-Sensitized Solar Cells

•IOP PEDOT film was synthesized as a counter electrode of DSSC.•Porous IOP electrode showed superior electrocatalytic activity.•Improvement of quantum efficiency was achieved by using IOP counter electrode.

An inverse-opal poly(3,4-ethylene dioxythiophene) (PEDOT) electrode was fabricated by electrodeposition of EDOT onto a PEDOT:poly(styrene sulfonate) filler in a self-assembled polystyrene template. By this novel fabrication method, the inverse-opal electrode was directly assembled into a dye-sensitized solar cell (DSSC) as a Pt-free counter electrode without any additional processing. This inverse-opal PEDOT electrode exhibits superior electrocatalytic activity and easy electrolyte diffusion in the electrode, as the inverse-opal electrode provides a porous morphology. The improved reflectivity of the inverse-opal electrode was also observed in the incident-photon conversion-efficiency spectra at low wavelength, which was a characteristic of its well-ordered structure. Therefore, the inverse-opal PEDOT electrode could successfully act as an alternative counter electrode for DSSCs to replace Pt in the counter electrode.