Synthesis of Mesoporous, Nanocrystalline Lanthanum Phosphate in the Presence of Citric Acid and Stearic Acid
来源期刊：JOURNAL OF RARE EARTHS2007年第6期
论文作者：Yusaku Takita Hiroyasu Nishiguchi Li-Ngee Ho Katsutoshi Nagaoka
Key words：mesoporous; lanthanum phosphate; citric acid; stearic acid; nanocrystalline; rare earths;
Abstract: Lanthanum phosphate was prepared in the presence of citric acid and stearic acid under methanolic conditions at pH 4.5 and pH 7, respectively.The samples obtained were intensively characterized using X-ray diffraction, nitrogen adsorption-desorption isotherm study, transmission electron microscopy (TEM), thermal gravimetric and differential thermal analysis, and Fourier transform infrared (FTIR) analysis .The as-synthesized samples prepared at pH 4.5 showed lamellar mesostructured form with high crystallinity.Results showed that the pore size and pore volume changed when the materials were prepared under different pH conditions.Morphology of the samples was observed by using TEM, which showed that the samples possessed relatively small particles closely packed together.The as-synthesized samples were investigated using FTIR, and the mesopore formation mechanism was discussed.
Yusaku Takita1，Hiroyasu Nishiguchi1，Li-Ngee Ho1，Katsutoshi Nagaoka1
(1.Department of Applied Chemistry,Oita University,Dannoharu 700,Oita 870-1192,Japan)
Abstract:Lanthanum phosphate was prepared in the presence of citric acid and stearic acid under methanolic conditions at pH 4.5 and pH 7, respectively.The samples obtained were intensively characterized using X-ray diffraction, nitrogen adsorption-desorption isotherm study, transmission electron microscopy (TEM), thermal gravimetric and differential thermal analysis, and Fourier transform infrared (FTIR) analysis .The as-synthesized samples prepared at pH 4.5 showed lamellar mesostructured form with high crystallinity.Results showed that the pore size and pore volume changed when the materials were prepared under different pH conditions.Morphology of the samples was observed by using TEM, which showed that the samples possessed relatively small particles closely packed together.The as-synthesized samples were investigated using FTIR, and the mesopore formation mechanism was discussed.
Key words:mesoporous; lanthanum phosphate; citric acid; stearic acid; nanocrystalline; rare earths;
【全文内容正在添加中】
