Feasibility of Removing LiI and I₂ from Traditional Iodine-Based Electrolyte in Dye-Sensitized Solar Cells

The conventional iodine-based electrolyte (I^-/I₃ ^-), with LiI and I₂ as key components, has long served as the benchmark redox couple in dye-sensitized solar cells (DSCs) owing to its high efficiency and rapid regeneration kinetics. However, its inherent drawbacks, including corrosion of metal electrodes (e.g., silver and platinum), significant open-circuit photovoltage (V _oc) loss, and competitive visible light absorption, impose limitations on the devices' long-term stability and performance ceiling. This study critically evaluates the feasibility of completely removing both LiI and I₂ from the electrolyte system. We first investigated whether the electrolyte can maintain effective carrier transport in the absence of I₂ and LiI. By systematically adjusting the concentration of iodine-containing ionic liquids, the types of organic solvents, and the formulation of other additives, this study successfully achieved a device efficiency of 8.82%, comparable with that of traditional I₂-based electrolytes. Our analysis confirms that the removal of iodine-based species is not only feasible but also represents a pivotal research direction for the advancement of DSC technology. The success of this paradigm shift hinges on the synergistic development of novel redox mediators, optimized electrolyte formulations, and tailored interfacial engineering to mitigate charge recombination.