杂化钙钛矿(HOC2H4NH3)2CuCl4的制备与表征

采用低温溶液法合成了新型层状有序的含有羟基的有机/无机杂化钙钛矿材料(HOC₂H₄NH₃)₂CuCl₄, 采用元素分析、红外光谱、紫外-可见光吸收光谱、X射线衍射和X射线吸收精细结构等手段对其结构与性能进行了表征。结果表明:该材料通过无机框架诱导有机组分有序排列, 形成了规则的层状结构, 有序性高。该杂化钙钛矿材料的分解温度为212℃, 电阻率为2.86×10⁶ Ω·cm, 比不含羟基杂化钙钛矿的电阻率低两个数量级。紫外-可见光吸收光谱显示285 nm左右有一归因于电子从Cl(3p)价带顶跃迁到Cu(4s)导带底而产生的吸收峰。X射线吸收精细结构谱图表明: 二维层状杂化钙钛矿晶体中的Cu²⁺与6个Cl^-形成八面体配位, Cu-Cl键长为0.191 nm, 层间距为1.099 nm。

Preparation and Characterization of a Novel Hybrid Perovskite (HOC2H4NH3)2CuCl4

A novel organic-inorganic hybrid material containing hydroxyl, (HOC₂H₄NH₃)₂CuCl₄ with perovskite structure, was synthesized by low-temperature solution method. The structure and properties of the hybrid material were characterized by elemental analysis, IR, UV-Vis absorption spectrum, X-ray diffraction, and X-ray absorption fine structure techniques. The result reveals that the hybrid material (HOC₂H₄NH₃)₂CuCl₄ is well-ordered and in two-dimensional layered frame, and the organic component is in orderly arrangement induced by inorganic framework. The decomposition temperature of the hybrid material is about 212℃, and the resistance of the hybrid material is about 2.86×10⁶ Ω·cm, which is two orders of magnitude less than hybrid perovskite without hydroxyl. UV-Vis spectra shows that the crystal has a new absorption peak at about 285 nm which is attributed to the electronic transitions from the top of the valence band of Cl (3p) to the bottom of the conduction band of Cu (4s). XAFS result shows that Cu²⁺ with six Cl^- forms octahedral coordination in the hybrid layered crystal with layer spacing of 1.099 nm, and the Cu-Cl bond length is about 0.191 nm.