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用化学共沉淀法制得掺有一定量锑离子的α－Ｆｅ２Ｏ３，超微粉料．ＴＧ－ＤＴＡ、ＸＲＤ及ＳＥＭ等分析表明，掺锑量（Ｓｂ／Ｆｅ原子比）小于０．２时，材料仍保持α－Ｆｅ２Ｏ３的晶体结构，但其晶化温度随Ｓｂ含量的增加向高温区移动；在低温段纯α－Ｆｅ２Ｏ３的晶粒生长活化能（Ｑ＝１０．３ｋＪ／ｍｏｌ）远小于Ｓｂ／Ｆｅ＝０．１（Ｑ＝３５．３ｋＪ／ｍｏｌ）粉料的活化能；Ｓｂ５＋取代α－Ｆｅ２Ｏ３晶粒中Ｆｅ３＋格位与在４５０℃下长期工作粉料颗粒不易长大，是造成掺锑α－Ｆｅ２Ｏ３元件电阻降低一个多数量级及气敏性能显著改善的主要原因．
Using chemical coprecipitation method was mixed with a certain amount of antimony-α-Fe2O3, ultrafine powder. The results of TG-DTA, XRD and SEM show that the crystal structure of α-Fe2O3 remains with the amount of antimony (Sb / Fe atomic ratio) less than 0.2. However, the crystallization temperature increases with the increase of Sb content (Q = 10.3kJ / mol) was much smaller than that of Sb / Fe = 0.1 (Q = 35.3kJ / mol) in the low temperature range; the activation energy of Sb5 + Fe3 + lattice in the α-Fe2O3 grains is not easy to grow with long-term working powder particles at 450 ℃, which is the main reason that the resistance of the antimony-doped α-Fe2O3 decreases more than one order of magnitude and the gas sensitivity significantly improves.