Interface modification stands out as a crucial method to enhance the performance of perovskite solar cells. This study explores the utilization of the ionic liquid 1-Methyl-3-propylimidazolium phosphate (MPIMPH), containing phosphate (PO43−) groups, as a modifier for SnO2/perovskite interfaces. Detailed investigations delve into the specific impact of IL MPIMPH on defects in tin dioxide, perovskite defects, perovskite crystallization, morphology, and overall device performance. Initially, Density Functional Theory (DFT) is employed to evaluate the defect passivation potential of different anions on tin vacancies within the SnO2 matrix, revealing the exceptional defect passivation ability of the PO43− group. Chemical interactions between ILs MPIMPH and SnO2, as well as perovskite, are confirmed, establishing a fundamental basis for interface defect passivation. ILs-based interface modification enhances interface contact, influencing the lead iodide conversion into perovskite and perovskite crystallization, ultimately leading to the formation of high-quality perovskite thin films. ILs also effectively suppress interfacial charge recombination and optimize the energy alignment of the SnO2/perovskite interface to enhance carrier extraction. Benefiting from the interface modification with ILs, the optimized device achieved an impressive device efficiency of 24.24 % with remarkable durability. This work provides an novel aspect for designing ionic liquids to enhance interface modification, contributing to upscaling and application of perovskite photovoltaics.

中文翻译：

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用于钙钛矿光伏中高级界面改性的磷酸盐离子液体：离子液体分子设计的新见解


界面修饰是提高钙钛矿太阳能电池性能的重要方法。本研究探索了利用含有磷酸盐 (PO43−) 基团的离子液体 1-甲基-3-丙基咪唑磷酸盐 (MPIMPH) 作为 SnO2/钙钛矿界面的改性剂。详细研究深入探讨了 IL MPIMPH 对二氧化锡缺陷、钙钛矿缺陷、钙钛矿结晶、形态和整体器件性能的具体影响。最初，采用密度泛函理论（DFT）来评估不同阴离子对SnO2基体中锡空位的缺陷钝化电位，揭示了PO43−基团卓越的缺陷钝化能力。 ILs MPIMPH 和 SnO2 以及钙钛矿之间的化学相互作用得到证实，为界面缺陷钝化奠定了基础。基于离子液体的界面修饰增强了界面接触，影响碘化铅转化为钙钛矿和钙钛矿结晶，最终形成高质量的钙钛矿薄膜。 IL 还可以有效抑制界面电荷复合并优化 SnO2/钙钛矿界面的能量排列以增强载流子提取。受益于 IL 的接口修改，优化后的器件实现了 24.24% 的令人印象深刻的器件效率，并且具有出色的耐用性。这项工作为设计离子液体以增强界面改性提供了一个新颖的方面，有助于钙钛矿光伏器件的升级和应用。