Influence of Ionic Liquid Electrolytes on the Photovoltaic Performance of Dye-Sensitized Solar Cells

Abstract

New binary ionic liquid electrolytes based on 1-methyl-1-butylpyrrolidinium bis(trifluromethylsulfonyl)imide, 1-butylpyridinium bis(trifluromethylsulfonyl)imide, 1-methyl-3-ethylimidazolium bis(trifluromethylsulfonyl)imide, 1-methyl-3-ethylimidazolium tetracyanoborate, or 1-methyl-3-ethylimidazolium tricyanomethanide coupled with 1-methyl-3-propyl-imidazolium iodide were developed for dye-sensitized solar cells (DSCs). We examined these ionic liquid compositions in conjunction in conjunction with a diketopyrrolopyrrole-based donor-π bridge acceptor dye (DPP-13) in dye-sensitized solar cells and also investigated the influence of adding lithium ions to the electrolyte to enhance the device performance. The best device exhibited a short-circuit current density of 15.2 mA cm−2, an open-circuit voltage of 678 mV, and a fill factor of 71 %, corresponding to an overall power conversion efficiency (PCE) of 7.1 % under standard AM 1.5G illumination at 100 mW cm−2.