"Nanotechnology and nanomaterials"

Studies of the influence of water molecules on the perovskite structure CH3NH3PbI3

Zelenyak T.Yu.1, Turchenko V.A,, Doroshkevich A.S.1,2, Gladyshev P.P.3, Shylo A.V.2, Stanculescu A.4, Balasoui M.1,5, Madadzada A.I.1,6, 
Asgerov E. B.1,6

1 Joint Institute for Nuclear Research, str. Joliot-Curie, 6, Dubna-141980, Russia.
E-mail:tatyana.zelenyak@bk.ru
2 Donetsk Institute for Physics and Engineering named after O O Galkin NAS of Ukraine, Prospect Nauki, 46, Kyiv-03680, Ukraine;
3 Dubna International University, st. Universitetskay, 19, Dubna-141980, Russia.
4 National Institute for Materials Physics (NIMP) Strada Atomiștilor 405, Măgurele 077125, Romania
5Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering (IFIN-HH), Bucharest Romania,
6National Nuclear Research Center, АZ-1073, Baku, Azerbaijan

The key problem of perovskite solar cells remains their instability in the environment. 

Fig. 1. X-ray diffraction patterns of experimental thin-film perovskite CH3NH3PbI3: 1 - 0 min on air; 2 - 24 hours in the air; 3 - after 72 hours in the air; 4, 5 are the intense peaks of the phases PbI2, CH3NH3PbI3.

	In this work, X-ray diffraction methods were used to study the change in the crystal structure of perovskite CH3NH3PbI3 films storing in air under normal physical conditions (Fig. 1). The established redistribution of the intensities of the (010) and (003) peaks indicates the monotonic degradation of the tetragonal phase and the corresponding perovskite structure of CH3NH3PbI3 storing. 
The study was performed in the scope of the Project of JINR – Romania  at 2020, order № 269, p 62.and order 268 п.59.