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本文以廉价的无机盐为原料，采用sol－gel法制备了Ce：Ti（摩尔比）为0．05～0．4：1之间的一系列CeO2－TiO2复合氧化物．利用物理吸附仪，XRD，TEM等手段对复合氧化物的织构和结构性质进行了表征．结果发现：采用无机盐－超临界流体干燥法可制备大孔、高比表面积的CeO2－TiO2复合氧化物，随着CeO2含量从5％增加到40％，复合氧化物的比表面积由67．3m2·g－1增加到219．4m2·g－1；物相由锐钛矿转变为无定形；粒体的粒径、形貌也随之变化，由颗粒状逐渐变为网络结构．而与超临界流体干燥得到的气凝胶相比；采用普通干燥法制备得到的复合氧化物具有较低的孔体积和比表面积，颗粒间团聚较严重，但无“孤岛”状大颗粒，晶相为无定型结构．
In this paper, a series of CeO2-TiO2 composite oxides with Ce: Ti (molar ratio) of 0.05-0.4: 1 were prepared by sol-gel method using cheap inorganic salts as raw materials. The texture and structure properties of the composite oxides were characterized by means of physical adsorption, XRD and TEM. The results showed that CeO2-TiO2 composite oxide with large pore area and high specific surface area could be prepared by inorganic salt-supercritical fluid drying method. With the increase of CeO2 content from 5% to 40%, the specific surface area of composite oxide increased from 67.3m2 · G-1 increased to 219.4m2 · g-1; the phase changed from anatase to amorphous; the particle size and morphology of the particles also changed from granular to network structure gradually. Compared with the aerogels obtained by the supercritical fluid drying, the composite oxide prepared by the ordinary drying method has lower pore volume and specific surface area, more agglomeration between particles, but no “island” Phase is amorphous structure.