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Measure is treasure: proper iodine vapor treatment as a new method of morphology improvement of lead-halide perovskite filmsтезисы доклада
- Авторы: Гришко А.Ю., Елисеев А.А., Гудилин Е.А., Тарасов А.Б.
- Сборник: II Московская осенняя международная конференция по перовскитной фотовольтаике (MAPPIC-2020): сборник тезисов, [электронное издание сетевого распространения] – М.: «КДУ», «Добросвет», 2020. – 87 с
- Тезисы
- Год издания: 2020
- Место издания: KDU Moscow
- DOI: 10.31453/kdu.ru.978-5-7913-1149-8-2020-87
- Аннотация: Halide perovskites AMX3 (A=CH3NH3+, (NH2)2CH+, Cs+, Rb+; M = Sn, Pb, X = Cl, Br, I) emerged as a new class of materials for optoelectronic applications in the last 12 years which triggered extensive investigations on their chemical and physical properties. Considering the pronounced effect that molecular oxygen exerts on physical properties of various oxide materials, it was to be expected that researchers would take an interest in deciphering the effect of molecular halogens (Cl2, Br2, I2) on halide perovskites. Several reports have shown that exposure of halide perovskites to molecular iodine can induce chemical transformations and tune physical properties of these materials. The experimental data available in the literature may be divided into three categories according to the partial pressure of iodine at a given temperature. At low iodine partial pressures (<10-2 mbar, RT - room temperature) iodine only affects defect concentration thus altering conductivity and luminescent properties. On the other hand, severe decomposition occurs under oversaturated iodine vapor pressure (~10 mbar, RT). However, the effect of exposure to molecular iodine under intermediate iodine pressure (~10-1 mbar at RT) has not been reported so far.In the present study [3] we show that there exist a range of conditions between these two extremes in which halide perovskites chemically absorb molecular iodine to form RPM. Once being formed, highly reactive liquid RPM activates mass transport and facilitates the recrystallization of perovskite grains. Furthermore, under proper conditions chemical sorption appears to be reversible and, once the excess of iodine is liberated from the system, the target perovskite structure is recovered with no signs of PbI2 or other decomposition products. By means of in-situ Raman spectroscopy we confirmed the formation of RPM during iodine-treatment of halide perovskites. Using scanning electron microscopy, x-ray diffraction, time-resolved photo-luminescence spectroscopy we showed that iodine-treatment is beneficial for the overall quality of perovskite thin films that were fabricated by means of classical solution-based approaches and result in increase of the average grain size, crystallinity, lifetime of charge carriers. A fine control of the iodine partial pressure, temperatures of the substrate and exposure duration allows to apply this method successfully to mixed-cation and mixed-anion perovskites relevant for photovoltaic applications thus proving the versatility of the iodine treatment approach.Research was financially supported by the Russian Science Foundation (Project № 18-73-10224). References[1]Petrov AA, Belich NA, Grishko AY, Stepanov NM, Dorofeev SG, Maksimov EG, Shevelkov AV, Zakeeruddin SM, Graetzel M, Tarasov AB, Goodilin EA. A new formation strategy of hybrid perovskites via room temperature reactive polyiodide melts. Materials Horizons. 2017;4(4):625-32.[2]Turkevych I, Kazaoui S, Belich NA, Grishko AY, Fateev SA, Petrov AA, Urano T, Aramaki S, Kosar S, Kondo M, Goodilin EA, Graetzel M, Tarasov AB. Strategic advantages of reactive polyiodide melts for scalable perovskite photovoltaics. Nature nanotechnology. 2019 Jan;14(1):57.[3]Grishko AY, Eliseev AA, Goodilin EA, Tarasov AB. Measure is treasure: proper iodine vapor treatment as a new method of morphology improvement of lead-halide perovskite films. Chemistry of Materials. 2020
- Добавил в систему: Гришко Алексей Юрьевич