ISSN 0003-701X, Applied Solar Energy, 2014, Vol. 50, No. 4, pp. 255–259. © Allerton Press, Inc., 2014. Original Russian Text © B.L. Oksengendler, O.B. Ismailova, M.B. Marasulov, I.Z. Urolov, 2014, published in Geliotekhnika, 2014, No. 4, pp. 55–59. 255 INTRODUCTION Among various problems of photovoltaics, most recently the special interest of researchers has been attracted to solar cells based on perovskites based on organic–inorganic components; in the most general terms this is CH 3 NH 3 PbJ 3 or close variants [1]. The start of the “perovskite era” (see [2]) occurred in 2009 [3]; then, over 2012–2013 the conversion rate of solar energy into electrical energy increased from 10% [4] to 15% [5]. To date, the characteristic physical and mechanical structure of a perovskite solar cell (Figs. 1a, 1b, 1c, 1d) has been formed, which is char- acterized by the corresponding electronic band struc- ture of the device (Fig. 1b). Along with excellent fea- tures of perovskite cells (inexpensive and relatively simple low-temperature technology and an under- standable physical chemistry of the components), some difficulties have been identified, whose solution could lead, according to some experts [2], to a “new On the Degradation Mechanism of Functioning Solar Cells Based on Organic–Inorganic Perovskites B. L. Oksengendler a , O. B. Ismailova b , M. B. Marasulov a , and I. Z. Urolov a a Institute of Polymer Chemistry and Physics, Academy of Sciences of the Republic of Uzbekistan, Uzbekistan b Institute of Ion-Plasma and Laser Technologies, Academy of Sciences of the Republic of Uzbekistan, Uzbekistan e-mail: oksengendlerbl@yandex.ru Received March 23, 2014 Abstract—This paper presents the first attempt to build a model and detect the degradation mechanism of organic–inorganic photovoltaic solar cells based on perovskites. The cross section of the process of the for- mation of a close Frenkel pair in the sublattice of iodine is obtained and its annealing channels are found. It is concluded that there is a nonmonotonic dependence of the stationary number of defects on the intensity of solar radiation, which allows one to analyze the properties of the radiation resistance of a device to ionizing radiation. DOI: 10.3103/S0003701X14040100 HELIOTECHNICAL MATERIALS SCIENCE (100 nm) Energy vacuum (c) (d) Au PCBM CH 3 NH 3 PbJ 3 PolyTPD PEDOT:PSS ITO (a) (b) (10 nm) (285 nm) (10 nm) (70 nm) ITO PEDOT:PSS –4.8 –2.4 –3.9 –5.4 –5.9 –5.4 –5.4 –5.3 –3.9 Au PC BM CH 3 NH 3 PbJ 3 PolyTPD OCH 3 O N N n Fig. 1. The scheme of a solar cell based on perovskite: (a) the geometric structure of layers; (b) the electronic structure of layers; (c) the chemical structure of polerelomin (polyTPD); (d) the chemical structure of PCBM (see [1–3]).