Polymer electrolyte based on polyethylene glycol for quasi-solid state dye sensitized solar cells

A gel polymer electrolyte containing I−/I3− redox couple was prepared using polyethylene glycol (PEG) as polymer matrix and propylene carbonate (PC) as organic solvent by sol–gel method. A dye sensitized solar cell (DSSC) employing the gel polymer electrolyte gives an open-circuit voltage of 0.7 V and a short-circuit current of 8.1 mA cm−2 at an incident light intensity of 100 mW cm−2. Fourier transform infrared spectroscopy was utilized to examine the chemical properties of produced gel electrolytes. Unlike the conventional covalent bond that bridges the different polymer segments, in this study, it was observed that hydrogen bonds bridged polyethylene glycol and propylene carbonate. Influences of different synthetic parameters such as reaction time and temperature were also investigated. Optimal DSSC performance was observed at electrolyte reaction temperature and time of 100 °C and 24 h, respectively, with a maximum photoelectric energy conversion efficiency of 2.2%.

► A new PEG-based gel polymer electrolyte containing I−/I3− redox couple was prepared.
► Synthetic parameter is a critical factor in preparing a gel electrolyte system.
► The cell efficiency is very sensitive to the length of the period during which the gel is formed.
► Under optimal conditions, the DSSC could attain PV efficiency about 2.2%.