ランタン(La)ドープシリカ(SiO2)多孔質複合体の合成と構造解析

Abstract

Silica containing Lanthanum (La) for the CO2 adsorption has been synthesized by a precursor solution method, involving heat treatment and reduction stages, and the dependence on La dose in the transformation of the crystal structure has been investigated systematically by X-ray diffraction (XRD). As a result, XRD pattern of many kinds of Silica specimens showed the broad pattern, which means amorphous structure, while only the high La contain silica specimen (Si : La = 2 : 1) demonstrated many peaks of La2O3. This finding suggested that little La atoms might replace into the site of Si with the Si-O network as a mechanism of the transformation of the crystallization during heat treatment, have little effect to determine the crystallization of silica. To make a characteristic micro-porous structure for the CO2 adsorption, the consisting of highly dispersed metallic La within a Si-O matrix should be necessary.