Effect of non-stoichiometry of initial reagents on morphological and structural properties of perovskites CH3NH3PbI3

Nanoscale Research Letters

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[1] 0000 0004 0385 8977, grid.418751.e, V.I. Vernadskii Institute of General and Inorganic Chemistry of the NAS of Ukraine, Kyiv, Ukraine;grid.466789.2, V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, Kyiv, Ukraine;

关键词: Metal halide perovskite;    Film;    Microstructure;    Chemical reaction;    Raman spectroscopy;    81.07.Pr;    81.07.–b;    81.70.Jb;    87.64.kp;   

DOI  :  10.1186/s11671-018-2841-6

来源: publisher

【 摘 要 】

The properties of films of organic-inorganic perovskites CH3NH3PbI2.98Cl0.02 depending on the ratio of starting reagents in solutions (PbI2:{CH3NH3I + CH3NH3Cl}) has been investigated. It was found that the formation of the perovskite structure with the ratio of the initial reagents PbI2: CH3NH3I = 1:1 occurs at 70–80 °C, and with the increase of the temperature of thermal treatment to 120 °C, the thermal destruction of the perovskite begins. When the ratio of the starting reagents PbI2: CH3NH3I = 1:2, the formation of the perovskite structure occurs through the intermediate compound (CH3NH3)2PbI4, and when the ratio is 1:3—(CH3NH3)3PbI5 and (CH3NH3)2PbI4. Independent on the ratio of the initial components (CH3NH3I:PbI2), the ratio between the content of lead and iodine in the films remains unchanged, that is why a significant difference in the film properties could be explained by the anisotropy of the particle shape, which is consistent with the data of electron microscopy and X-ray diffractometry.

【 授权许可】

CC BY