Photoelectrochemical solar cells with polyacrylonitrile-based and polyethylene oxide-based polymer electrolytes

Two types of photolectrochemical (PEC) solar cells, FTO/TiO2/dye/PAN, EC, PC, Pr4N+I−, I2/Pt/FTO, and FTO/TiO2/dye/PEO, EC, PC, KI/I2/Pt/FTO have been fabricated using a PAN-based gel polymer electrolyte and a PEO-based plasticised polymer electrolyte. The PAN-based gel electrolyte, made of polyacrylonitrile (PAN), ethylene carbonate (EC), propylene carbonate (PC) and tetrapropylammoniumiodide (Pr4N+I−) as the complexing salt exhibited a room temperature conductivity of 2.9×10−1 S m−1 for the composition, PAN (13%):EC (31%):PC (45%):Pr4N+I− (7%):I2 (4%) by weight ratio. The PEO-based polymer electrolyte had a conductivity of 2.2×10−3 S cm−1 for the composition PEO (37.5%):EC (37.5%):PC (20.7%):KI (3.9%):I2 (0.4%). These solar cells have been characterised using current–voltage characteristics and action spectra. The PAN-based solar cells had an overall quantum efficiency of 2.3%. However, the PEO-based solar cells had an overall quantum efficiency of only 0.6%.