SiO2粉体制备及其与Ag2S复合工艺研究

Study on Synthesis of SiO2 Powders and Its Combining Processes with Ag2S

采用改性Stober法来可控制备SiO2粉体,并探究了不同沉淀剂对SiO2粉体形貌及粒径大小的影响。分别采用水热法、溶剂热法和沉淀法来制备SiO2/Ag2S复合粉体,并使用XRD、SEM-EDS、NanoMeasure等手段对制备出的各种粉体的物相、成分、形貌和粒径分布等进行表征与分析。结果表明,以正硅酸乙酯(TEOS)为硅源,氨水为沉淀剂时,添加适量聚丙烯酸酯乳液可有效控制SiO2微球的粒径;以碳酸钠水溶液为沉淀剂时,能得到线状SiO2粉体。在140℃下水热处理6 h得到的SiO2/Ag2S粉体的复合效果较好;常温下,通过热处理共沉淀出的SiO2/Ag2S粉体具有操作简便、反应条件易控制、复合效果较好等优点。

SiO2 powders with controllable particle size were prepared by a modified Stober method,and effects of different control agents on the morphology and particle size of SiO2 powders were investigated.SiO2/Ag2S composite powders were also obtained from hydrothermal method,solvothermal method and precipitation method.The phase,composition,morphology and particle size distribution of SiO2 and SiO2/Ag2S powders were characterized and analyzed by means of XRD,SEM-EDS and NanoMeasure.Results show that the particle size of SiO2 microspheres with ethyl orthosilicate(TEOS)as silicon source and ammonia as the precipitation agent can be effectively controlled by adding appropriate amount of polyacrylate emulsion.Linear SiO2 powder can be obtained when sodium carbonate aqueous solution is used as the precipitation agent.SiO2/Ag2S composite powders obtained from water heat treatment at 140℃ for 6h have a good composite effect.SiO2/Ag2S powders prepared by heat treatment coprecipitation have advantages of simple operation,easy control of reaction conditions and good composite effect.