| IV-VI compounds are semiconductor materials with a cubic structure and narrow band gap. PbS and PbSe semiconductor materials have a wide application prospect in the infrared optical detection, photovoltaic conversion, solar cells, nonlinear optical materials, optoelectronic devices, sensors and detectors, and some other high-tech fields as a result of their excellent electrical and optical properties. In this work, two kinds of semiconductor material were synthesized by four simple technological processes. A series of analytical methods including:X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and fluorescence spectrometer were used to characterize the crystalline phase, microstructure, and optical properties of as-synthesized samples. Based on experimental results and optimization of synthesis processes, the properties of products were further improved.PbS micron cube structure, PbS nanowires, and PbS nano-structural network were prepared via chemical vapor deposition (CVD) under different experimental conditions. Through studying the effects of reaction temperature and reaction time on the products, the optimum experimental conditions were found, under which the micro-nano cube structural PbS was prepared at a reaction temperature of 650℃for 10min. For PbS nanowires preparation, elevated reaction temperature or prolonged reaction time result in a change for PbS from nanowires to micrometer cubic structure; nano-Au catalyst was more favorable to the formation of PbS nanowires than the nano-Ag. Flows of H2 had impact on the network structure of PbS products and the optimum H2 flow was 1sccm for preparing PbS network nanostructures in the quartz tube whose diameter is 4.3cm. We found that photoluminescence properties of PbS nanowires was better than PbS micron cube structureand PbS nano-structural network, and the photoluminescence of PbS nano-structured network was the weakest among the three.Through studying the effects of surfactant and reaction time on product formation, the flower-like PbS and star-like PbS were prepared via microwave method in an autoclave with the assistance of cetyltrimethylammonium bromide (CTAB). The optimal conditions of rapid preparation for flower-like structural PbS and star structural of PbS were obtained. Through the analysis of the reaction processes, the formation mechanisms for the flower structural PbS and star structural PbS were discussed. And photoluminescence properties of the flower-like structure of PbS and star structural of PbS were discussed by fluorescence spectrometer and photoluminescence properties of star-shaped structure PbS was weaker. In addition, PbS nanoparticles were prepared in a condensate reflux device under the assistance of microwave radiation. Compared with traditional preparation methods, this method showed advantages such as simple devices, short time-consuming, high quality and yield. This is a feasible preparation method for semiconductor nanomaterials.The cube PbS was prepared by solvothermal method, microstructures and crystalline structures of as-synthesized PbS products were characterized and analyzed by field emission scanning electron microscopy, and X-ray diffraction. The effects of reaction temperature, reaction time, and the source molar ratio of sulfur to lead on the morphology were discussed.As the biologically induced mothed is getting much attention for its environmental protection and economic benefits, egg membrane was introduced into this work to synthesize face-centered cubic structural PbSe at room temperature. Meanwhile, the effect of aging of selenium source solution on product formation was investigated. The aging of Se source resulted in obvious encapsulation of the egg membrane, and this phenomenon led to orderly binding reaction of lead ions and selenium ions so that PbSe nano-materials were synthezised with a relatively good dispersion stability.
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