Efficient, stable, and flexible dye-sensitized solar cells based on nanocomposite gel electrolytes

• Mechanically pressed, binder-free TiO2 films from pastes as flexible photoanodes
• Nanocomposite gel electrolytes to improve sealing constraints and durability
• Solar to electric energy conversion efficiency of 6.49% was achieved.
• Thermal stability of nanocomposite gel electrolytes was discussed.

We have fabricated efficient and stable full-plastic dye-sensitized solar cells (DSCs) based on nanocomposite gel electrolytes. Different compositions of binder-free nanocrystalline TiO2 pastes combined with mechanical compression technique were employed to prepare TiO2 photoanodes on indium-doped tin oxide coated polyethylene naphthalate. The performance and durability of plastic-based DSCs using nanocomposite gel electrolytes which contain ceramic nanoparticles in 3-methoxypropionitrile (MPN)-based or binary ionic liquid electrolytes were investigated. The results show that the compressed photoelectrode composed of commercial titanium powders P25 and 100 nm TiO2 powders in conjunction with a TiO2 solidified MPN-based nanocomposite gel electrolyte achieved an energy conversion efficiency of 6.49%. Moreover, the DSCs based on TiO2 solidified bi-IL electrolyte were found to provide better durability than MPN-based nanocomposite gel electrolyte, whereas the efficiency maintained > 97% of its original efficiency after 500 h of aging test under continuous light irradiation (100 mW cm− 2) at 60 °C.