Ionic liquids (ILs) are gradually becoming relevant within the efforts towards more stable perovskite solar cells, either by their incorporation into the perovskite active layer or as an interfacial additive. In this work, we synthesized the ionic liquid tetrabutylphosphonium iodide and applied it as an additive at the interface between the electron selective contact – mesoporous – TiO₂ and the perovskite CH₃NH₃PbI₃ active layer. Specific conditions of tetrabutylphosphonium iodide (B₄PI) interfacial modification resulted in an improved device stability and a reduction of the hysteretic behavior suggesting a possible passivation of trap states and/or mitigation of ionic migration phenomena.

离子液体（IL）通过将其纳入钙钛矿活性层或作为界面添加剂，逐渐成为更稳定的钙钛矿太阳能电池的重要组成部分。在这项工作中，我们合成了离子液体四丁基碘化膦，并将其作为添加剂应用于电子选择性接触介孔TiO 2_和钙钛矿CH ₃ NH ₃ PbI ₃活性层之间的界面。四丁基碘化鏻 (B ₄ PI) 界面改性的特定条件导致了器件稳定性的提高和滞后行为的减少，这表明可能会钝化陷阱状态和/或减轻离子迁移现象。