Polyiodide solid-state dye-sensitized solar cell produced from a standard liquid I−/I3− electrolyte

Abstract

Solid-state dye-sensitized solar cells were obtained by drying a standard I⁻/I₃⁻ liquid-electrolyte cell in ambient conditions. Slow evaporation of the organic solvent allows the formation of a polyiodide (I_n⁻, n ≥ 3) network that bridges the counter electrode and dye/TiO₂ layer. The unsealed polyiodide solar cell (Ply-I DSSC) with 5T dye reaches a maximum of 5.2% peak power conversion efficiency (peak PCE), similar to the precursor liquid-state solar cell (Liq-I DSSC) of maximum PCE = 5.7%. Once the performance of the Ply-I DSSCs reaches a stabilization (stb.) point (maximum stb. PCE 5.0%), no loss in performance is displayed under dark storage in ambient air without any encapsulation for a period of around 10 months.