The Preparation And Characterization Of Cuprous Doping Hybrids （R-NH₃）₂Sn_1-xCu_xI_4-x Through Solvothermal Method

The layered perovskite-type organic-inorganic hybrids are one of new materialsthat sort of the assembly of the organic and inorganic units on the molecular scale.SnI2-based layered perovskite-type organic-inorganic hybrids are naturalquantum-well semiconductor materials which may contain the excellent properties ofboth organic materials and inorganic materials. These materials have a great potentialapplication in the field of microelectronics.SnI2-based layered perovskite-type organic-inorganic hybrids not only have theproperty of semiconduction that inorganics possess,but also be formed film easily like organics, it can be made into a large area of thin film by the simple process in low cost at the room temperature,so this material has a great potential applications in the field of microelectronics.But the hybrid material can’t fully meet the application requirements at present, because of its low mobility ratio,low carrier concentration and largeband gap.so the main direction of this material research is to looking for a high mobility ratio,high carrier concentration of new hybrid material.It has important significance for its practical application to reduce the band gap effectively.This dissertation focused on doping cuprous into iodide stannous based hybrids(R-NH3)2Sn1-nCunI4-n, among kinds of organic amine, β-Phenylethylamine,4-FluorinePhenylethylamine and4-Chlorobenzene Ethylamine, respectively. In order to improvethe carrier concentration through cuprous doping and lower the band gap through theintroduction of organic units with halogen. The dissertation has used the solvothermalmethod to prepare the target products and researched the synthesis of target productsunder different cuprous doping amount to obtain the best synthesis process. Andstudied the structure and properties of the products, investigated the influence to theband gap with different cuprous doping amount and different kind of organic units.The results prove that using solvothermal method can synthesis doping cuprousinto iodide stannous based hybrids with typical lamellar structure. The cuprous dopingamount has much improved contrast with the normal liquid phase method, but, thecuprous doping amount is still difficult to precise control. The structural analysisprove that the interlayer spacing between two adjacent titanium calcium depositschanges when the organic units change. What’s more, the interlayer spacing increasesaccording to sequence of β-Phenylethylamine,4-Fluorine Phenylethylamine and4-Chlorobenzene Ethylamine. But, the value is not consistent with the predictionvalue. It illustrates that the spatial arrangement of different organic units in hybrids is different. And it leads to the difference of interaction between organic and inorganicunits, therefore, the bond length and bond angle of inorganic layer changes along withthe change of organic units, so as the hybrids band gap. Uv-vis absorption spectrashowed that the band gap takes no significant impact on the system because of thelow cuprous doping amount. But, when the organic units change, the band gapchanges, and absorption edge has obvious red shift with the introduction of halogen.The band gap is about1.78eV of β-Phenylethylamine, the band gap is about1.3eV of4-Fluorine Phenylethylamine, and the band gap is about1.45eV of4-ChlorobenzeneEthylamine. It shows that the introduction of organic halide in the organic units caneffectively reduce the band gap. Whereby, when the halogen elements is fluorine, ithas big electronegativity, and stronger electronic absorption ability, effectively reducethe interaction between organic and inorganic units, more reduced the inorganic layeroctahedral distortion, therefore, effects of the band gap decreased more significantly.