纳米复合铁-硅氧化物的制备、性能及其应用  

Preparation and catalytic properties of nanosized γ-Fe_2O_3 composite oxides

作　　者：李雅莉[1] 白守礼[2] 闫涛[2] 陈霭璠[2] 

机构地区：[1]唐山职业技术学院,河北唐山063000 [2]北京化工大学理学院,北京100029

出　　处：《北京化工大学学报（自然科学版）》2005年第2期77-80,共4页Journal of Beijing University of Chemical Technology(Natural Science Edition)

基　　金：国家自然科学基金(20377004);北京市自然科学基金(2032014)

摘　　要：用溶胶凝胶法制备了纳米γFe2O3及γFe2O3/SiO2复合氧化物,以透视电镜(TEM)、热重差热分析(TG DTA)、BrunauerEmmettTeller(BET)分析和X射线衍射分析(XRD)对纳米粒子进行表征,以CH4为模型反应,在固定床流动反应器中对复合氧化物进行催化活性评价,并制作了气敏元件。考察了γFe2O3及γFe2O3/SiO2敏感元件对CO和其他还原性气体的灵敏度及焙烧温度对敏感度的影响,得到对CO检测的合适焙烧温度分别为500℃和600℃和最佳操作温度310℃。结果表明,γFe2O3/SiO2纳米复合氧化物中SiO2对γFe2O3的相变温度、加强热稳定性及提高气体灵敏度起到较大的作用。The nanostructured γ-Fe_2O_3 and it's complex oxides were prepared by a sol-gel method from Fe(NO_3)_3·9H_2O and (C_2H_5)_4SiO_4 precursors. The particles size, thermal stability, specific surface and the crystal phase morphology were systematically characterized by TEM, TG-DTA, BET and XRD. The catalytic activity for methane combustion in a fixed-bed reactor under atmospheric pressure and the sensitivity of the sensing element made of γ-Fe_2O_3 and γ-Fe_2O_3/SiO_2 for CO and other reducing gases were tested. The effects of the calcination temperature on the sensitivity were also examined. The results show that the addition of SiO_2 is a very important factor for enhance of the phase change temperature, thermal stability and the sensitivity of γ-Fe_2O_3.

关 键 词：纳米氧化物 FE2O3 气体灵敏度 催化活性 相变温度 

分 类 号：TQ138.11[化学工程—无机化工]