Fabrication and Characterization of Bifacial Dye-Sensitized Solar Cells Utilizing Indoline Dye with Iodine- and Cobalt-Based Redox Electrolytes

Bifacial solar cells are gaining popularity due to their compactness, space-saving property, and higher photoconversion efficiency (PCE) than mono-facial solar cells. Bifacial dye-sensitized solar cells (BF-DSSCs) are fabricated and characterized utilizing D-205 as a dye sensitizer in combination with I-/I3- and Co2+/Co3+ redox electrolytes. BF-DSSCs using iodine-based electrolytes demonstrate a cumulative PCE and bifaciality factor (BFF) of 13.05% and 85%, respectively. The hampered PCE under backside light illumination is attributed to the absorption of photons by the electrolyte itself. Contrary to this, BF-DSSCs fabricated using cobalt-complex-based redox electrolyte exhibits an exceptionally high BFF of nearly 100% with a PCE of 4.77% and 4.75% under the front- and rear-light illumination, respectively. Although the open-circuit voltage of the BF-DSSCs fabricated using cobalt electrolyte (with deeper redox potential) is slightly higher than that of BF-DSSCs fabricated using iodine electrolyte, their cumulative PCE (9.52%) is much lower than that of iodine-based device counterparts (13.05%). This decrease in PCE is attributed to the relatively fast charge recombination in the cobalt-electrolyte-based BF-DSSCs. In this study, the effect of bifaciality factor on bifacial dye-sensitized solar cells utilizing D-205 as a dye sensitizer in combination with I-/I3- and Co2+/Co3+ redox electrolytes is reported.image (c) 2023 WILEY-VCH GmbH