Synthesis of Organic-Inorganic Perovskite CH3NH3PbI3 using Dimethyl Sulfoxide (DMSO) Solvent

P. V. Torchyniuk1

O. I. V’yunov1*Email

A. A. Ishchenko 2

I. V. Kurdyukova2 

A. G. Belous1

1 V.I. Vernadsky Institute of General and Inorganic Chemistry of the NAS of Ukraine, Kyiv, Ukraine

2 Institute of Organic Chemistry, NAS of Ukraine, Kyiv, Ukraine

Abstract

Organic-inorganic perovskites are unstable materials to external conditions that prevent their widespread use to convert solar energy. Changing the starting reagents ratio and the solvent can affect the structural and electrical properties of perovskites. Films of organic-inorganic perovskites CH3NH3PbI3 at different ratios of starting reagents (PbI2:CH3NH3I) in solvent DMSO has been synthesized. It was found that regardless of the initial reagent ratio (1:1, 1:2, 1:3), the formation of perovskite occurs in similar schemes: through the formation of four intermediate compounds (CH3NH3)2(DMSO)xPbI4, (CH3NH3)2(DMSO)2Pb3I8, PbI2·2DMSO, PbI2·DMSO. It was found that the use of DMSO and the ratio of initial reagents 1:3 at the synthesis of organic-inorganic perovskite leads to the formation of more stable films compared with the use of DMF solvent. It was found that under the influence of moisture for 80 days, perovskite films obtained at a ratio of 1:2 and 1:3 in DMSO, were degraded by 45 and 22%, respectively. The films obtained in DMF at a ratio of 1:2 and 1:3 were degraded by 62 and 57%, respectively. This difference shown is associated with the formation of different intermediate phases, which are templates in the crystallization of perovskite.

Synthesis of Organic-Inorganic Perovskite CH3NH3PbI3 using Dimethyl Sulfoxide (DMSO) Solvent