Efficient and stable hybrid perovskite prepared at 60% relative humidity with a hydrophobic additive in anti-solvent

• Published in: Solar energy materials and solar cells Vol. 215; p. 110625
• Main Authors: Arias-Ramos, Carlos Fabián, Kumar, Yogesh, Abrego-Martínez, Paola Gabriela, Hu, Hailin
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15-09-2020; Elsevier BV
• Subjects: Acetic acid; Ambient fabrication; Anti-solvent; Commercialization; Efficiency; Ethyl acetate; Humidity; Hydrophobic additive; Hydrophobicity; Perovskite solar cells; Perovskites; Photovoltaic cells; Photovoltaics; Pyridines; Relative humidity; Solar cells; Solvents; Thin films; Hydrophobic additive; Ambient fabrication; Perovskite solar cells; Anti-solvent
• ISSN: 0927-0248; 1879-3398
• DOI: 10.1016/j.solmat.2020.110625

The use of controlled inert ambient to produce hybrid perovskite solar cells (PSCs) makes them less competitive towards the commercialization. Herein, progress is made with the preparation of hybrid perovskite (CH3NH3PbI3) in a high relative humidity (RH ~ 60%) ambient condition by using a mixture of ethyl acetate (EA) and 4-Tertbutyl-Pyridine (tBP) as anti-solvent. A small amount of tBP helps to form a more homogeneous perovskite surface with a higher hydrophobicity. The mixture of EA and tBP is found to be an efficient anti-solvent to extract the primary solvent and moisture in the precursor solution and form mirror-like perovskite thin films. More than 200 perovskite solar cells, with active area of 0.1 cm2, were prepared with the perovskite thin films prepared under ambient conditions. It is showed that a small amount of tBP in EA improves consistently all the photovoltaic parameters of our PSCS, from an average efficiency of 8.64% over 113 cells with only EA as anti-solvent to 13.64% over 131 cells with EA + tBP as the anti-solvent. More than 55% of the last ones show efficiencies higher than 16%. The champion cell, recording an efficiency of 17.41% in the beginning and reaching the maximum efficiency of 18.04%, remains more than 80% of the initial efficiency after more than 180 days of storage in ambient conditions without encapsulation. The proposed method opens the possibility to fabricate highly efficient and stable perovskite solar cells under ambient condition without glove box.
•Homogeneous perovskite thin films can be prepared in high relative humidity ambient.•4-Tertbutyl-Pyridine in ethyl acetate as anti-solvent increases the hydrophobicity of perovskite.•High efficient and stable perovskite solar cells can be produced in ambient conditions.•About 80% of retain in cell's efficiency is achieved after 6 months of storage without encapsulation.