A novel gel polymer electrolyte based on polyacrylonitrile (PAN) and its application in a solar cell

A PAN-based gel polymer electrolyte with possible iodide ion conductivity was prepared by incorporating a mixture of Pr4N+I−, iodine, EC and PC in PAN. Out of various compositions prepared and characterised, the sample with composition PAN (13%):EC (31%):PC (45%):Pr4N+I− (7%):I2 (4%) by weight ratio, exhibited the maximum room temperature (25°C) conductivity of 2.95×10−3 S cm−1. The predominantly ionic nature of the electrolyte was established by using the dc polarisation technique. The temperature dependence of ionic conductivity follows the VTF behaviour, indicating the amorphous nature of the electrolyte. Dye-sensitised photoelectrochemical solar cells prepared using this electrolyte exhibited an open circuit voltage (Voc) of 0.69 V, a short circuit current (Isc) of 3.73 mA cm−2 for an incident light intensity of 600 W m−2 yielding an overall quantum efficiency of 2.99%.