Stable dye-sensitized solar cells based on a gel electrolyte with ethyl cellulose as the gelator

Abstract

A simple gelating process is developed for the conventional acetonitrile-based electrolyte of dye solar cells, based on ethyl cellulose as the gelator. The electrolyte becomes quasi-solid-state upon addition of an ethanolic solution of ethyl cellulose to the conventional acetonitrile-based liquid electrolyte. The photovoltaic conversion efficiency with the new gel electrolyte is only slightly lower than with the liquid electrolyte, e.g., 6.5 % for liquid electrolyte versus 5.9 % for gel electrolyte with 5.8 wt% added ethyl cellulose. Electrolyte gelation has small effect on the ionic diffusion coefficient of iodide, and the devices are remarkably stable for at least 550 h under irradiation at 55°C.

Biopolymer-Based Electrolytes for Dye-Sensitized Solar Cells: A Critical Review

“…Addition of 10 wt % EC reduced the microcracks in the ZnO film, which increased the fill factor and thus the efficiency of the DSSC up to 3.8%. However, utilization of EC as an electrolyte instead of photoanode resulted in better performing DSSCs as reported by Vasei et al They jellified the liquid electrolytes consisting of LiI, I 2 , 4-butylpyridine, and tertbutyl ammonium iodide by adding EC. Insertion of EC increased the viscosity of the gel 300 times compared to pristine electrolyte, resulting in a decrease in photovoltaic performance of the DSSC from 6.5% to 5.8%.…”

“…From the beginning of polymeric electrolyte application in DSSCs, synthetic polymers have been used extensively in pristine, mixed, and composite forms including nanocomposites of many inorganic additives. ,− Some of the most commonly used synthetic polymers for the preparation of electrolytes are poly­(ethylene oxide), ,,− ,− poly­(propylene oxide), − poly­(acrylonitrile), − poly­(butyl acrylate), , poly­(methyl methacrylate), poly­(vinyl chloride), , poly­(vinyl pyrrolidinone), − poly­(vinylidene fluoride), − and poly­(vinylidene fluoride-hexafluoropropylene). − However, as these polymers are synthetically manufactured and not ecofriendly, recently much attention has been given to the possible application of biopolymers in DSSCs. Among many biopolymers, polysaccharides like cellulose, − carrageenan, ,− agarose, ,−…”