Imimdazolium-Based Ionic Liquid-Controlled Synthesis Of ZNO Micro/Nano-Crystals

Room temperature ionic liquids (RTILs), emerging environmental friendly solvents, have so many merits comparing with the traditional solvents. RTILs have been successfully applied in catalytic chemistry, organic synthesis, electrochemical researches and extraction separation. With the increasing type and the intensified research, the ranges of application of RTILs are also constantly expanding. Because RTILs have more advantages than traditional solvents during the synthesis process, it provides a new route for the synthesis of inorganic nano-materials. There are, however, a few reports about the application of RTILs in the inorganic nano-material synthesis. Consequently, searching for an optimal condition of RTILs in synthesizing inorganic nano-materials has a good guide for the future research. In this work, a chemical synthesis method was proposed, and the different morphologies, uniform particle size and well dispersed crystal particles of ZnO were successfully synthesized in the presence of RTILs.The project is supported by Grant 20973055 (from the National Natural Science Foundation of China). The main contents of the thesis are summarized as followed:(1) The synthesis of RTILs of [C_nmim] X (n = 2, 4, 6, 8, benzyl; X = Br^-, Cl^-), [C_nmim] Y (n = 4, 6, 8, benyl; Y = BF₄^-) according to the literature reported.(2) The micro/nano-particles of ZnO with various morphologies were prepared using the different kinds of RTILs by non-toxic, environmental friendly, fast and green chemical methods. The X-ray diffraction (XRD), scanning electron microscopy (SEM), Ultraviolet–visible spectroscopy (UV-Vis) and photoluminescence (PL) were used to study the effects of the reaction temperature, the reaction time, the concentration of Zn(Ac)₂·2H₂O, the kind and the amount of RTILs on the morphology and structure of ZnO products.(3) The mechanism of different ZnO particles morphologies was proposed based on the effects of the e experimental conditions on the morphology of micro/nano-particles of ZnO.(4) The reductive activity of nano/micro particles of ZnO were studied by the catalytic degradation of Rhodamine B solution. It was found that the catalytic degradation rate is changed with the conditions of ZnO preparation. The ZnO prepared by [C8mim]Br degrade Rhodamine B solution was much faster than the ZnO prepared by [C₆mim]Br.