METHOD OF MAKING INORGANIC CHLORINE-CONTAINING PEROVSKITE THIN FILMS Russian patent published in 2020 - IPC C01G21/16 C01D17/00 C30B29/12 

FIELD: synthesis of inorganic materials.

SUBSTANCE: invention relates to synthesis of inorganic materials, particularly to production of perovskite thin films, which can be used as an active layer for light-emitting diodes and solar cells. Method of making inorganic chlorine-containing perovskite thin films by chemical anion exchange in vapor phase involves obtaining a sample of a perovskite thin film of composition CsPbBr₃ deposited on a substrate, placed next to a second clean substrate in a vessel with a flat bottom, heated to 120 °C for at least 3 minutes. Then, hydrochloric acid (HCl, 40 %) is applied on a clean substrate and both pads are covered with a cover heated to 120 °C, the transverse dimension of which is less than the transverse dimension of the vessel with a flat bottom, wherein the amount of the deposited acid and the size of the cover is selected in an approximate volume ratio of 1:2,500, and the time of the anion exchange reaction is selected depending on the required ratio of bromine and chlorine in the manufactured film of composition CsPbBr_3-xCl_x (0≤x≤3), taking into account that the time for complete substitution of halogens Br on Cl does not exceed 3 minutes, after which the obtained sample is heated by raising temperature from 120 °C to 200 °C for 2 minutes.

EFFECT: technical result consists in the possibility of performing the procedure in a closed medium, which makes the process safe, in obtaining any ratio of halogens in a short period of time and maintaining high-quality morphology of perovskite films.

1 cl, 1 dwg, 1 ex