Synthesis And Properties Of Sulfide Nanomaterials Assisted By Melon Rings

The aim of this dissertation is to study the synthesis of Q[6]-CdS composite photocatalyst with potential application value by using cucurbit[6]uril(Q[n] or CB[n], n=6) as modifier. Cd S with a narrow band gap so that it can u se visible light photocatalytic and have broad application prospects in the field of photocatalysis. The properties of the materials were greatly influenced by the morphology and size of the nanoparticles; therefore, it is very important to study the surface modification of the nanoparticles. The hydrogen bonding, dipole-ionic, coordination, interaction of back models of cucurbit[n]urils with metal ion, and can be used as modification agent or carrier in the preparation of the nanometer materials. Based on the special structure and properties of cucurbit[n]urils, we will choose to design and synthesis cucurbit[6]uril modified cadmium sulfide and in order to achieve the aim of controlling the morphology, particle size and photocatalytic performance of the products. In this work, Q[6]-CdS composite photocatalysts were prepared by chemical precipitation method, hydrothermal method and ultrasonic method with cucurbit[6]uril(Q[6]) as modifier, in order to obtain high catalytic activity of photocatalyst. The main research contents are as follows:1. Q[6]-Cd S composite photocatalysts were prepared by chemical precipitation method with thioacetamide as sulfur source, cucurbit[6]uril as modifier. The effects of the amount of Q[6], metal doping and reaction time on the morphology and photocatalytic properties of the products were investigated. The products were characterized by X-ray diffraction(XRD), Fluorescence spectrometer(PL), Fourier Transform Infrared Spectroscopy(FT-IR), scanning electron microscope(SEM) et al.The results shown that when the amount of Q[6] is 0.15 mmol, the reaction time is 7 h, the obtained Q[6]-CdS composite photocatalyst was better for the degradation of methylene blue. In addition, the photocatalytic performance of Q[6]-CdS composite photocatalyst was further improved by doping Co and Ce.2. Q[6]-Cd S composite photocatalysts were prepared by hydrothermal method. The effects of sulfur sources(sodium thiosulfate, thioacetamide, thiourea and L-cysteine) on the structure and properties of the products were investigated. The structure of products were characterized by XRD, FT-IR and SEM. Q[6]-Cd S with different structures and morphologies were obtained, and the performance of photocatalytic degradation of methylene blue was also studied. The results shown that the Q[6]-CdS composite photocatalysts has better photocatalytic performance compared to the Cd S. When L-cysteine as sulfur source, the obtained Q[6]-CdS composite photocatalyst showed an effective degradation rate in 100 min.3. Q[6]-Cd S composite photocatalyst was synthesized by ultrasonic method with thioacetamide as sulfur source, cucurbit[6]uril as modifier. The structural and catalytic performances of the products were studied by a variety of methods. The similarities and differences of Q[6]-Cd S composite photocatalysts obtained by three methods were compared. The results shown that the Q[6]-Cd S prepared by ultrasonic method has the photocatalytic efficiency compared with the chemical precipitation method.The use of modifier Q[6] promotes the separation of the electron hole pair in Q[6]-CdS, Q[6]-CdS composite photocatalysts with high catalytic activity were obtained by controlling the main factors that affect the properties of Q[6]-CdS.