Investigation on Various Polymer Electrolytes for Development of Dye Sensitized Solar Cell

Dye sensitized solar cells (DSSCs) based on TiO2 nanoparticles film have attracted extensive attention from both industry and academia. Generally, the liquid electrolyte is used in dye sensitized solar cells, but the vaporization of liquid electrolyte hinders its commercialization as its affects its stability. And also the reduction in performance of dye sensitized solar cells was observed due to electron recombination in semiconductor liquid electrolyte interfaces. The situation worsens when the photoanode is in contact with the vaporization of electrolyte solution that affects the charge distribution at the semi conductor electrolyte interface and initiates photo corrosion on the photoanode. With the finding of ionic conductivity in polymer, electrolytes complexed with salt give a breakthrough to the development of DSSC devices. Various types of electrolytes have been developed and tested in different DSSCs configurations to overcome this problem. Among all polymer electrolytes, PEO (Polyethylene oxide) based polymer electrolyte has shown excellent performance in different electrochemical application areas. In DSSCs, it is also considered a novel candidate due to its excellent ability to form complexes with ionic salts. Poly(vinyl alcohol) (PVA) is also a promising candidate acting as a host polymer due to its inherent characteristics like high mechanical strength, good tensile strength, high temperature resistance, non toxicity, good optical properties and high hydrophilicity. PVA have a large extent of poly hydroxyl group, which makes PVA highly hydrophile. It also offers other advantages like excellent chemical stability, ease of preparation, and flexibility. In the present paper, we review different types of polymer electrolytes which have been used for improving the performance and stability of DSSCs.