Ionic liquids for efficient and stable perovskite solar cells: A comprehensive review
Subject Areas : Synthesis and Characterization of Nanostructures
Mohammad Saeed Rajabzade
1
,
Karim Abdizadeh
2
,
Fariba Tajabadi
3
,
Nima Taghavinia
4
1 - Center for Nanoscience and Nanotechnology, Sharif University of Technology, Tehran, Iran.
2 - Department of Materials Science and Engineering, Sharif University of Technology, Tehran, Iran.
3 - Department of Nanotechnology and Advanced Materials, Materials and Energy Research Center, Karaj, Iran.
4 - Nanoparticles and Coatings Lab, Department of Physics, Sharif University of Technology, Tehran, Iran.
Keywords: Ionic liquids, Perovskite solar cell, Green solvents, Solar cell fabrication process, Passivation.,
Abstract :
Perovskite solar cells have rapidly advanced in power conversion efficiency, reaching over 26% at the laboratory scale. However, transferring these impressive efficiencies to durable, large-scale devices remains a major challenge. A key bottleneck lies in the fabrication of high-quality perovskite layers, which typically relies on toxic and volatile solvents and additives that hinder scalability and long-term stability. Ionic liquids have been proposed as a versatile class of materials to overcome these challenges. Fundamentally, ionic liquids are organic salts that remain liquid at or near room temperature, characterized by negligible vapor pressure, thermal stability, and solubility. This review article provides a comprehensive perspective on the role of ionic liquids in perovskite photovoltaic technology. It examines the key applications and mechanisms by which ionic liquids enhance perovskite film quality, including controlled crystallization kinetics and defect passivation. Various synthesis and integration techniques for fabricating efficient perovskite solar cells without the use of toxic antisolvents are discussed in detail. Performance improvements and stability enhancements are also highlighted: ionic-liquid-engineered perovskite solar cells demonstrate efficiencies comparable to the best existing solar cells (20–24%) and exhibit significantly longer operational lifetimes under stress conditions. Through an analysis of recent studies, this review underscores that ionic liquids are not only suitable replacements for volatile solvents but also multifunctional additives capable of unlocking new levels of efficiency and stability in perovskite solar cells.
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