A major challenge for outdoor uses of methylammonium lead halide (MAPbX3) solar cells is the poor durability of the perovskite film under humidity. This instability is due to limitations of the dipping or spin coating process in producing MAPbX3 films through a direct reaction between PbI2 and methylammonium iodide (MAI) in an organic solvent. In this study, we devised an eco-friendly and cost-effective method to fabricate MAPbX3 films using an aqueous solution of Pb(NO3)2 and MAI vapour. I | Cite this paper Vietnam J. Chem. 2023 61 S2 81-87 Research Article DOI A novel eco-friendly film preparation process for improving the stability of organometal halide perovskite in solar cells Thuy Thanh Thi Nguyen1 2 Minh-Hang Nguyen1 2 Phi-Hong Nguyen1 2 Thuy Thanh Doan Nguyen1 2 Tien Huu Nguyen1 2 Phuong Tuyet Nguyen1 2 1 Faculty of Chemistry University of Science Ho Chi Minh City 227 Nguyen Van Cu District 5 Ho Chi Minh City 70000 Viet Nam 2 Vietnam National University Ho Chi Minh City 227 Nguyen Van Cu District 5 Ho Chi Minh City 70000 Viet Nam Submitted February 19 2023 Received May 30 2023 Accepted July 1 2023 Abstract A major challenge for outdoor uses of methylammonium lead halide MAPbX3 solar cells is the poor durability of the perovskite film under humidity. This instability is due to limitations of the dipping or spin coating process in producing MAPbX3 films through a direct reaction between PbI2 and methylammonium iodide MAI in an organic solvent. In this study we devised an eco-friendly and cost-effective method to fabricate MAPbX3 films using an aqueous solution of Pb NO3 2 and MAI vapour. In both instances of using Pb NO3 2 and PbI2 a perovskite layer with a tetrahedral structure was seen with a band gap of roughly eV. We discovered that the perovskite film grew at a slower rate with aqueous Pb NO3 2 compared to that in PbI2 and disintegrated gradually at ambient temperature and 40 humidity. Compared to PbI2 films-based solar cells under the same reaction time those based on aqueous Pb NO3 2 films showed remarkably higher durability maintain 83 for Pb NO3 2 films-based 78 for PbI2 films- based after 720 hours and greater photovoltaic efficiency with the photocurrent density of the voltage of V the fill factor of and PCE of which is higher than PbI 2 cells 30 . Keywords. Perovskite solar cells organometal halide perovskite stability vapour deposition. 1. INTRODUCTION and chemical .
