| Metal-containing ionic liquid crystals(MILC) have attracted great attention because their unique properties and versatile potential applications.The aim of this thesis is to construct a series of metal-containing ionic liquid crystals employing ionic liquids and to characterize their properties and structures,in addition,to study the application about the in-situ preparation of semiconductor nanoparticles by using perovskites templates. There are three main experimental studies included in this thesis.In the first part,perovskite-type MILCs are synthesized by reactions between 1-hexadecyl-3-methyl-limidazolium bromide(chloride) and corresponding metal halides. The structured thin-films are obtained by spin-coating method.The purity and molecule composite of the products are measured by elemental analysis technique.The measurements of X-ray diffraction,Fourier transform infrared spectra and differential scanning calorimetry are used to analyze the formation of hydrogen bond,the layer structure and the thermal properties of products.Transmission electronic microscope methods are applied to characterize the semiconductor nanoparticles morphologies after the reacting of perovskite-type MILCs template with H2S gas.It was shown that[C16-mim]2[CuCl4]and[C16-mim]2[ZnCl4]can form SmA phase along with slowly heating,while[C16-mim]2[CuBr4]melted into a optically isotropic liquid.The reason for the formation of SmA phase maybe due to the van der Waals interaction,which increases with the length of the alkyl chain,leading to the increase of the whole molecule's polarizabillity and intermolecular laterial attraction.Meanwhile, intermolecular's tail attraction reduces with the decrease between the tail of alkyl chain CH3- and high polarizabillity aromatic ring reduces with the chain length increase.When the alkyl chain length n=16,the intermolecular laterial attraction is dominant,the segregation of the aliphatic parts prevails over other noncovalent interactions,the SmA phase formed.But Brleads to the dispersion of electronic distribution,then the whole molecule's polarizabillity reduced,and the segregation of the aliphatic parts is not obvious,so[C16-mim]2[CuBr4]didn't show SmA phase. The nanoparticles are prepared by reactting the copper bromide layered perovskite template with H2S gas.The nanoparticles' diameters are about 1～2 nm,and no aggregation is found for them.However,The morphology of ZnS nanoparticles is filar clusters nanostructure when the zinc chloride layerd pervoskite template is used.These results showed the influence of anions on the template structure and morphology of nanomaterials.The second part,perovskite-type MILCs based on pyridinium are prepared by convenient and feasible method.The influence of different metal ions on their structure, properties,especially liquid crystal phases is studied.The influence of the template on the synthesis of nanoparticles was also investigated and some results are achieved.Their thermal behavior has been investigated by differential scanning calorimetry and hot-stage polarizing optial microscopy.On heating,[C16-Py]2[CuBr4]didn't show birefringence phenomena and has a short melting range.It means that[C16-Py]2[CuBr4] can't form liquid crystal.It can be applied as the liquid crystal material's additive for its low melt point and the hysteresis when cooling from isotropic liquid into solid.From the TEM image,anion ions influence the product morphologies.Aggregation of PbS nanoparticles are heavier with the longer reaction time.CuxS formed by perovskite layer structure[C16-Py]2[CuBr4]as template,the unformed structure morphology of CuxS changed to spherical particles.ZnS nanoparticles' morphology is the aggregate like willow leaf,This nanoparticles' morphology maybe because that the different contact areas between the core of particles and H2S gas led to the different growing rates.A part of region's growing rate is faster than the other part's.The template deformed partly for forming the aggregation.The last part,the effects of the alkyl chain length,metal ionic categories and halide ionic kinds on the structure and property of perovskite-type MILCs based on ammonium are investigated.Thermogravimetric analysis and differential scanning calorimetry revealed a reversible solid-solid phase transitions,which exhibit fairly large enthalpy change.Solid-solid phase transitions are caused by the distortion of organic ammonium cation,in which the two-dimensional order structure changing into disordered.And the products' decomposition temperatures are relatively lower,they decompose before transition to the isotropic liquid.The nanoparticles are prepared by reacting bis(n-alkylammonium) tetrahalometallates layered perovskite template with H2S gas.The similar morphology of nanoparticles are generated from the templates with different thickness,though the nanoparticles aggregate and show a little larger diameter under dilute solution template conditions.Thanks for the supports from the National Natural Science Foundation of China.(20373035,20573066,20773080)...
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