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用共沉淀法制备了ＳｎＯ２／ＦｅＯ３ 纳米复合粉体，用Ｘ 射线衍射（ＸＲＤ） 、Ｍｓｓｂａｕｅｒ 谱研究了它的物相、晶粒度及变化过程。结果表明，煅烧温度在７００ ℃以下时，它可能是以四方ＳｎＯ２ 纳米晶为主体（ 其平均粒径为３－０ｎｍ） ，α－ Ｆｅ２Ｏ３ 纳米晶包裹在ＳｎＯ２ 晶界的复合相，其中α－ Ｆｅ２Ｏ３ 结晶很不充分，５４－７ ％ 聚集于晶界。这种复合相的结构阻碍了ＳｎＯ２ 晶粒的长大，有利于煅烧后保持纳米晶结构。
SnO2 / FeO3 nanocomposite powders were prepared by coprecipitation method. The phase, grain size and the change of SnO2 / FeO3 nanocomposites were investigated by X-ray diffraction (XRD) and Mssssauer spectrum. The results show that when the calcination temperature is below 700 ℃, it may be composed of tetragonal SnO2 nanocrystals (average particle diameter of 3-0nm), α-Fe2O3 nanocrystal wrapped in the SnO2 grain boundary composite phase, wherein α-Fe2O3 Crystallization is not sufficient, 54-7% gathered in the grain boundary. The structure of this composite phase hinders the growth of SnO2 grains, which helps to maintain the nanocrystalline structure after calcination.