(江西理工大學(xué) 冶金與化學(xué)工程學(xué)院,贛州 341000)
摘 要: 采用溶膠-凝膠法制備鈣鈦礦型LaFe1-x-yMgxNiyO3的化合物,并利用TG-DTA、XRD、SEM和XPS等對其進行分析和表征。結(jié)果表明:摻雜樣品在0.2~2 μm波段的紅外發(fā)射率較未摻雜的LaFeO3的紅外發(fā)射率大幅度提高,其原因在于,摻雜離子取代鐵離子進入LaFeO3晶格中,為保持化合物電價平衡,部分Fe3+轉(zhuǎn)變?yōu)镕e4+,引入雜質(zhì)能級,氧空位濃度增加,促進雜質(zhì)能級吸收和氧空位吸收;摻雜引起的晶格畸變使得晶格振動吸收增強;此外,電子在Fe3+和Fe4+之間的極化躍遷,亦極大地提高摻雜鐵酸鑭的紅外輻射性能。
關(guān)鍵字: 鈣鈦礦;鐵酸鑭;摻雜;吸收率;紅外發(fā)射率
(College of Metallurgical and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China)
Abstract:A perovskite LaFe1-x-yMgxNiyO3 compound was prepared by the sol-gel method and characterized by TG-DTA, XRD, SEM, and XPS. The result shows that the infrared emissivity of the doped samples in the range of 0.2–2 μm is greatly improved than that of the undoped LaFeO3 sample. The increase of infrared emissivity of samples can be mainly attributed to the substitution of the doped ion with Fe3+ in the LaFeO3 lattice. In order to keep the balance of electrovalent compound, the substitution of the ion doping with Fe3+ introduces the energy level of Fe4+ impurity and generates oxygen vacancies, thus increasing the impurity and oxygen vacancy absorption. The lattice distortion caused by doping strengthens the lattice vibration absorption. Furthermore, the polaron hopping of electrons between Fe3+ and Fe4+ also significantly strengthens the absorption properties within the infrared radiative properties of doped lanthanum ferrite.
Key words: perovskite; lanthanum ferrite; doping; absorptivity; infrared emissivity


