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以Ce2(CO3)3,La2O3和Mn(NO3)2为原料,用“溶胶-凝胶”法结合“超临界干燥”技术,将铈掺入超细LaMnO3+λ气凝胶中。用TG-DTA,XRD,TEM,FT-IR等手段对样品进行表征;并用“2CO+2NO=2CO2+N2”反应测试铈掺杂对超细LaMnO3+λ催化活性的影响。结果显示:260℃时,镧铈锰气凝胶为疏松、絮状且具有较好分散性的棕色粉末,由大量直径小于10 nm的球形颗粒组成;850℃热处理后,镧铈锰气凝胶为粒径小于20 nm的类球形颗粒,晶相成分为LaMnO3+λ,La2O3和CeO2;铈掺杂增加LaMnO3+λ晶格的氧空缺数量,改善氧化还原催化的气氛条件,提高超细LaMnO3+λ的催化活性。
Using Ce2 (CO3) 3, La2O3 and Mn (NO3) 2 as raw materials and incorporating “sol-gel” method and “supercritical drying” technology into the ultra-fine LaMnO3 + airgel . The samples were characterized by means of TG-DTA, XRD, TEM and FT-IR. The effect of cerium doping on the catalytic activity of ultrafine LaMnO3 + λ was also tested with “2CO + 2NO = 2CO2 + N2” reaction. The results show that the lanthanum cerium-manganese airgel is a loose, flocculent and dispersible brown powder at 260 ℃, consisting of a large number of spherical particles with diameter less than 10 nm. After heat treatment at 850 ℃, LaMnO3 + λ, La2O3 and CeO2. The cerium doping increases the number of oxygen vacancies in the LaMnO3 + λ lattice, improves the atmosphere conditions for the redox catalysis and improves the microstructure of the ultrafine LaMnO3 + λ catalytic activity.