Composite poly(ethylene oxide) electrolyte modified with ethanol for dye-sensitized solar cells

The composite poly(ethylene oxide) PEO/TiO₂/KI/I₂ in acetonitrile has been introduced as a solid electrolyte for dye-sensitized solar cells (DSSCs). In this work, the influence of ethanol and water as additives in the composite electrolyte on conductivity and photoelectric performance of quasi-solid-state dye-sensitized solar cells will be presented. The average overall energy conversion efficiencies (%) of DSSCs using the composite PEO electrolyte in acetonitrile, acetonitrile with ethanol additive (10% v/v) and acetonitrile with water additive (10% v/v) were 5.60, 5.81 and 2.11, respectively. The ethanol content in acetonitrile was varied to achieve maximum conductivity and energy conversion efficiency. It was found that DSSC composed of the composite PEO electrolyte in 20% v/v ethanol in acetonitrile solution gave the best overall energy conversion efficiency of 6.33%. The long-term storage at room temperature demonstrated that the energy conversion efficiencies of DSSCs gradually decreased to 1% after 2,000 hours.