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以烷基紫精(alkylviologens;又称紫精或紫罗精)为有机客体、层状五氧化二钒为无机主体,在液、固两相反应体系中,利用I-与V5+的氧化还原反应,使烷基紫精阳离子通过静电引力作用进入被还原的五氧化二钒层板之间,形成一系列新颖的无机-有机插层化合物.并运用X射线粉末衍射(XRD)、红外(FT-IR)、X射线光电子能谱(XPS)、紫外-可见漫反射(UV-visDRS)等方法对其进行了表征.XRD分析结果证明,五氧化二钒的层间距随着烷基紫精中烷基链的增长而增大,但其结晶度随着烷基紫精阳离子中烷基链的增加而降低.XPS研究表明,该类材料中的钒是以V4+和V5+两种混合价态存在,氧原子处于三种不同的化学环境,这些现象说明烷基紫精阳离子的引入对五氧化二钒的骨架结构影响不大,主体五氧化二钒的层状结构保存完好;氮原子处于两种不同的化学环境,证实插层化合物中主客体之间相互修饰的协同效应,有可能起到了稳定客体分子激发态的作用,同时FT-IR光谱中芳香环特征谱带强度的变化也进一步证明了这一结论.UV-visDRS分析发现由于主客体的相互作用使插层化合物在紫外和可见光区域产生特殊的光吸收性质.从磁性研究的结果可以看出,在温度低于15K时,插层化合物RV2为反铁磁性的有序结构;当温度高于15K时,转变为顺磁性,表现出磁无序结构.
Using alkylviologens (also referred to as viologen or viologen) as an organic guest and layered vanadium pentoxide as an inorganic host, a redox reaction of I- with V5 + is performed in a liquid-solid two-phase reaction system Alkylation of alkyl viologen into the reduced vanadium pentoxide layer by electrostatic attraction to form a series of novel inorganic-organic intercalation compounds. X-ray powder diffraction (XRD), infrared (FT- IR, X-ray photoelectron spectroscopy (XPS) and UV-vis diffuse reflectance spectroscopy (XRD) .The XRD results showed that the interlayer spacing of vanadium pentoxide But the degree of crystallinity decreases with the increase of alkyl chains in alkyl viologen.XPS studies show that the vanadium in this kind of materials exists in two mixed valence states of V4 + and V5 + Oxygen atoms in three different chemical environments, these phenomena indicate that the introduction of alkyl viologen has little effect on the vanadium pentoxide skeleton structure, the main vanadium pentoxide layered structure is well preserved; nitrogen atoms in two different Chemical environment, confirmed the intercalary compound between the host and guest repair each other The synergistic effect may have the effect of stabilizing the excited state of the guest molecules, and the change of the intensity bands of the aromatic rings in the FT-IR spectrum further proves this conclusion.UV-visDRS analysis found that due to the interaction between host and guest The intercalation compounds have special optical absorption properties in the UV and visible region.It can be seen from the results of the magnetic studies that RV2 is an antiferromagnetic ordered structure at temperatures below 15K and at temperatures above 15K , Transformed into paramagnetic, showing a magnetic disordered structure.