Effect of additive polarity on the stability of organic-inorganic hybrid CH3NH3PbI3 perovskite thin film

Abstract

Synthesis of organic-inorganic hybrid CH3NH3PbI3 perovskite thin film from Pb(NO3)2 precursor was carried out by using alcohol with various polarity (isopropanol, 1-butanol and 1-propanol) as the additive. Preparation of CH3NH3PbI3 perovskite thin film was conducted by firstly forming Pb(NO3)2 thin film as the film’s precursor using spin coating method at 2500 rpm for 30 s with DMSO as the main solvent and isopropanol, 1-butanol or 1-propanol as the solvent additives. Pb(NO3)2 thin film was immersed in methyl ammonium iodide solution for 30 min to produce CH3NH3PbI3 perovskite thin film. The effect of solvent additive polarity on the grain size of perovskite film was studied using electron microscope method. Stability of CH3NH3PbI3 perovskite thin film was studied by using XRD and SEM. The result showed that increasing polarity of the solvent additives resulted in decreasing on the crystallinity of Pb(NO3)2 thin film. Pb(NO3)2 thin film with low crystallinity yielded high purity of CH3NH3PbI3 perovskite thin film with grain size up to 2.45 μm and have good stability with 43.09% degradation percentage for 24 h.