摘要
采用sol-gel法制备Fe、Fe-Ni离子B位掺杂的LaAlO3基红外辐射陶瓷材料,通过XRD、FTIR、SEM、IR-2、XPS等手段对掺杂试样进行表征分析。研究结果表明,掺杂后所得产物皆为钙钛矿结构复合氧化物,掺杂Fe后红外发射率有所提高但增加幅度较小,Fe-Ni共掺试样的红外辐射性能明显改善。当Fe3+掺杂量x=0.25时,在3~5μm波段的红外发射率从0.345提高到了0.821。红外发射率提高的物理机制在于:B位掺杂后存在产生氧空位和化学价变化两种补偿机制。化学价变化可产生Ni 3+Ni 2+和Fe3+Fe2+等小极化子,有助于电子从价带到导带的跃迁;随着氧空位浓度的增加,吸附氧比例增大,有利于提高材料在近中红外波段的吸收性能。因此,铝酸镧型材料作为炉窑的内衬材料可提高炉内辐射传热,具有广阔的应用前景。
LaAlO3 infrared radiation ceramic materials doped with Fe ion and Fe-Ni ions in B site were prepared with sol-gel method.The doped LaAlO3 samples were characterized and analyzed by XRD,FTIR,SEM,IR-2,XPS and other means.The results show that all the doped products are perovskite type complex oxides.The infrared emissivity is increased but the increment is small after Fe doping,and the infrared radiation properties are obviously improved after Fe-Ni co-doping.When the doping content of Fe^3＋is 0.25,the infrared emissivity within 3~5μm waveband increases from 0.345 to 0.821.The physical mechanism of the enhancement of infrared emissivity is as follows.There are two compensation mechanisms including the generation of oxygen vacancy and the change of chemical valence after B-site doping.The chemical valence change can produce small polarons from Ni ^3＋Ni 2＋and Fe^3＋Fe2＋,which is contributed to the transition of electrons from the valence band to the conduction band.With the increase of oxygen vacancy concentration,the ratio of the adsorbed oxygen increases,which is beneficial to improve the absorption properties of the ceramic materials in near mid-infrared waveband.Thus,lanthanum aluminate material as the lining material of furnaces can improve the radiation heat transfer in the furnace,and has a broad application prospect.
作者
常晴
李江霖
刘庆生
游拯
CHANG Qing;LI Jiang-lin;LIU Qing-sheng;YOU Zheng(College of Metallurgy and Chemical Engineering,Jiangxi University of Science and Technology,Ganzhou 341000,China)
出处
《稀有金属与硬质合金》
CAS
CSCD
北大核心
2018年第4期43-49,共7页
Rare Metals and Cemented Carbides
基金
国家自然科学基金(51264011
51564019)
关键词
铝酸镧
B位掺杂
SOL-GEL法
红外发射率
红外辐射
陶瓷材料
lanthanum aluminate
B- site doping
sol- gel method
infrared emissivity
infrared radiation
ceramic material
作者简介
通讯作者：刘庆生（1975一），男，博士，副教授，主要从事红外辐射节能材料研究，E-mail：397176537@qq．com
