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In recent decades, the scholars of the sulfur cadmium selenide ceramic pigments have done a lot of research in a variety capable of producing scarlet hue of pigment, the only sulfur cadmium selenide can produce pure red. Sulfur cadmium selenide poor thermal stability, decomposition easily oxidized at high temperatures. The bright red pigment has been how to get the high-temperature ceramic decorative direction of research topics. Chinese and foreign ceramics experts invest a lot of manpower, material and financial resources, trying to burn out people dream big red porcelain, but are not particularly successful, not high temperature ceramic bright red pigment, when the temperature rose to 600 ° C or more, the big red all faded, sulfur cadmium selenide solid solution into a mixture of cadmium sulfide and cadmium selenide, cadmium sulfide can be oxidized under high temperature, cadmium oxide and selenium dioxide, and thus lose its coloring. The production of high-quality porcelain firing temperature is generally above 1200 ℃, which produced huge temperature difference contradictions. Can burn out bright red porcelain heat resistance above 1200 ℃, which is a major scientific and technological challenges placed in front of the ceramic experts at home and abroad. In response to this problem, we take the wet synthetic nano-sulfur cadmium selenide, by forming a stable solid melt and parcel of the way, by the addition of zinc ions to form a solid solution, serve to improve the sulfur cadmium selenide decomposition temperature, then add the silicic acid sol, and nano-silica particles wrapped thereon, to achieve the purpose of the sulfur cadmium selenide solid melts can withstand high temperatures, and the ultimate success of resistance obtained particle size of less than 100 nanometers high temperature sulfur selenide, cadmium scarlet ceramic pigments. This thesis work include: 1, the preparation of the precursor of the red pigment: the first zirconium oxychloride and sodium silicate to prepare a sol, and then in the strict control of the pH of the system and under stirring, the previously prepared sulfur selenium The cadmium containing Zn2 suspension sol reaction. As the zirconium hydroxide and silica precipitation are transformed by a sol precipitated once particles are nano-level, so that the synthesis of zirconium silicate in the nanoscale particles, it is possible to reduce the generation temperature of the zirconium silicate. According to the mechanism of nucleation of the zirconium silicate, and the specific properties, experiments show that the generation temperature of the zirconium silicate plus the amount of auxiliary agents in the sol reloading Zn2, be calcined together with the precursor can be further reduced. 2, refractory the Scarlet ceramic pigment generated precursor into the ceramic crucible, put in a muffle furnace and heated to 350 ℃ insulation, allows the silicic dehydration; then the temperature was raised to 550 ℃ insulation sulfur cadmium selenide crystal The transformation is completed, prior to the formation of zirconium silicate and zirconium hydroxide is decomposed at this temperature, ready for the synthesis of zirconium silicate. The product was then loaded into a graphite crucible, maintained in a closed environment in the muffle furnace was raised to 850 ℃ for cadmium selenide zirconium silicate and sulfur to generate a solid solution, i.e. sulfur selenide, cadmium red nano pigment. The pigment can be tolerated 1200 ℃ high temperature, and can stably exist in a 1200 ° C oxidative atmosphere. Sol coprecipitation method, combined with the adjuvants and Zn2 successfully synthesized at a lower temperature than ideal zirconium silicate and sulfur cadmium selenide solid solution of the red pigment. The 3 sulfur selenide, cadmium red pigment Characterization of infrared spectroscopy, the precursor was heated to 850 ° C in a muffle furnace and incubated to generate a solid solution of Cd (SxSe1-x), and zirconium silicate. X-ray diffraction, scanning electron microscopy results, obtained using the method red ceramic pigment particle size between 20-30nm, belonging to the amorphous state is solid melts.
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