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以硝酸镧、硝酸铜、硝酸锶为原料,采用溶胶-凝胶法制备LaSrCuO4粉体,重点考察了柠檬酸(CA)与乙二胺四乙酸(EDTA)的摩尔比、溶液pH值、烧结温度等工艺参数对LaSrCuO4粉体形貌及相结构的影响。利用X射线衍射(XRD)、扫描电镜(SEM)及能谱仪(EDS)对粉体进行了相应的表征。结果表明:当n(CA):n(EDTA)=1.5:1、pH=9、烧结温度为800℃时得到了较高纯度、呈介孔结构的LaSrCuO4粉体;而当烧结温度为1000℃、EDTA添加量为零时得到的粉体呈片层状结构,添加EDTA时形成介孔结构粉体。介孔结构的形成机理是在表面活性剂EDTA分子与各种无机盐离子之间靠协同模板作用形成液晶相,然后进一步缩聚形成介孔结构。
LaSrCuO4 powder was prepared by sol-gel method using lanthanum nitrate, copper nitrate and strontium nitrate as raw materials. The molar ratio of citric acid (CA) to ethylenediaminetetraacetic acid (EDTA), the pH value of the solution, the sintering temperature Effect of Technological Parameters on Morphology and Phase Structure of LaSrCuO4 Powder. The powders were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). The results showed that LaSrCuO4 powders with higher purity and mesoporous structure were obtained when n (CA): n (EDTA) = 1.5: 1, pH = 9 and sintering temperature was 800 ℃. When the sintering temperature was 1000 ℃ , When the amount of EDTA is zero, the powder obtained has a lamellar structure, and mesoporous structure powder is formed when EDTA is added. The formation mechanism of mesoporous structure is to form a liquid crystal phase by a synergistic template between the surfactant EDTA molecule and various inorganic salt ions and further polycondensation to form a mesoporous structure.