乳液法结合溶胶-凝胶法制备氧化铝多孔微球

Preparation of Al_2O_3 Porous Microspheres via an Emulsion Method Combined with a Sol-gel Method

以仲丁醇铝为铝源、聚乙烯吡咯烷酮(PVP)为相分离诱导剂,采用水包油乳液法结合溶胶-凝胶法制备了氧化铝多孔微球,并利用FT-IR、SEM、TG-DTA以及XRD等测试技术对其显微结构进行表征。结果表明,所制得氧化铝微球成球性良好,添加PVP后对氧化铝微球的外观形貌没有影响,但对微球内部结构有很大影响,未添加PVP的氧化铝微球内部为实心结构,而添加PVP后则在微球内部形成独立的封闭大孔结构。随着热处理温度的增加,物相变化为无定形→γ-Al2O3→α-Al2O3。

Alumina porous microspheres were prepared by oil-in-water emulsion combined with a sol-gel method, with aluminum sec-butoxide as aluminum source and polyvinylpyrrolidone(PVP) as phase separation inducer. The morphology and structure of alumina porous microspheres were characterized by FT-IR, SEM, TG-DTA and XRD. The results show that the resulting alumina microspheres possess a superior spherical shape. The addition of PVP has no effect on the morphology of the alumina microspheres, while changs the internal structures of the microspheres. Alumina microspheres obtained in the absence of PVP possess a solid internal structure, while the addition of PVP leads to the formation of independent closed macropores in the microspheres. With the increase of heat-treatment temperature, the phase transition of the samples is amorphous Al2O3→γ-Al_2O_3→α-Al_2O_3.