Towards green, efficient and durable quasi-solid dye-sensitized solar cells integrated with a cellulose-based gel-polymer electrolyte optimized by a chemometric DoE approach

An innovative biopolymer composite electrolyte for dye-sensitized solar cells (DSSCs), obtained by quasi-solidifying an indigenous liquid electrolyte containing supporting salts and I3−/I− redox couple with a mixture of polyethylene oxide (PEO) and carboxymethyl cellulose sodium salt (CMC) is proposed. This is the first ever report indicating the useful aspects of CMC as a component in the electrolyte of a photovoltaic device and the requisite parameters are thoroughly investigated. Moreover, the performances of the lab scale quasi-solid devices are presented by means of a combined photovoltaic-chemometric approach, definitely innovative for the study of polymer based electrolytes for DSSCs. We also present the durability of the devices inherited by different PEO : CMC ratios as well as the response of the cells to various wavelengths and irradiation intensities. The intriguing photovoltaic-chemometric approach allows developing a device with efficiencies up to 5.18% under 1 sun irradiation (∼7% under 0.4 sun). The cumulative effect by the strategic components employed in the gel-polymer electrolyte demonstrates an outstanding durability with an excellent efficiency as high as 98% even after 250 h of extreme aging conditions.