| Organic-inorganic hybrid optoelectronic materials with layered perovskite structure represent a new class of materials that may combine desirable physical properties characteristic of both organic and inorganic semiconductor within a single composite. The hybrid materials can alternate chemically and electronically at the molecular level. In this thesis, we reviewed the crystal structures and physical properties and summed up the techniques of growing hybrid perovskites single crystals and thin films. It demonstrates a promising application prospect in optoelectronic devices field and enormous commercial market, and thus the materials have recently received substantial attention.(C4H9NH3)2CuCl4 which is a representation of hybrid perovskites was prepared via the reaction between copper chloride and butylammonium chloride, whose chemical structure was characterized by FT-IR and elemental analysis. Its thin film was obtained by spin-coating, and X-ray diffraction (XRD) measurements indicated the formation of two-dimensional layered quantum well structure, with the c-axis perpendicular to the substrate surface. It is seen that (C4H9NH3)2CuCl4 exhibits two distinct absorption bands centered at 286 and 384 nm which are due to a photoinduced exciton formed in the two-dimensional inorganic layers sandwiched between the organic layers.In order to investigate the relationship between the hybrid perovskite structure and the properties we fabricated a series of alkylammonium copper chloride hybrid perovskite, (C4nH8n+1NH3)2CuCl4(n=1, 2, 3), and studied the influence of changes of organic layer structure on the performance of the hybrid perovskites. In the series of compounds, the FT-IR spectra and X-ray diffraction curves changed with the variation of the alkyammonium chain length n, but the locations and shapes of UV-Vis absorption remained invariant. With increasing carbon chain length n in these compounds, the organic chains became more ordered and the intensities of hydrogenbonding increased, leading to the increasing of the interlayer distances. The organic chain tilt angle from the normal to the layers was estimated about 43.9° from the observed changes of the interlayer distance as a function of the alkyl chain length.Next, the change of inorganic layer from CuCl2 to ZnCl2 was adopted and a series of alkylammonium zinc chloride hybrid perovskite (C4nH8n+1NH3)2ZnCl4(n=1, 2, 3) was prepared. The corresponding influence on the structure and the perfomance of hybrid perovskites has also been investigated. Compared to that of C4CUCl4, the organic chain of the C4ZnCl4 was more ordered, the intensities of hydrogen bonding increased, and the stretching vibration peaks and bending vibration peaks of NH3+ groups shift to high frequencies. In addition, the temperature during solid-solid phase transition is relatively high, and both the entropy change and enthalpy change during the transition are smaller than those of C4CUCl4. These differences can be attributed to different metal ion coordination, because copper cation adopt an octahedral anion coordination, while zinc cation adopts an tetrahedron anion one.Finally, hybrid perovskites based on IV A metal halide were studied. For the perovskite of (C4H9NH3)2PbCl4, strong UV-Vis absorption at 332 nm was observed, and the full width at half maximum is narrow. While for (C12H25NH3)2SnI4, strong visible absorption at about 580 nm can be found indicating the narrow band gap of the hybrid perovskite.All these basic research results are of fundamental significance to both preparation of hybrid perovskites based on more complicated organic ammounium and modern optoelectronic devices from these organic-inorganic composite thin films.
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