La2O3对ZnO-SiO2纳米复合物结构性能的影响

采用溶胶-凝胶法制备了ZnO-SiO2和ZnO-La2O3-SiO2复合物,通过TEM分析发现其均为纳米颗粒,平均粒径分别为45nm和35nm;通过比表面及孔径分布测定发现ZnO-SiO2的比表面积高达715.5m2/g,La2O3的加入使其比表面积骤减至142.5m2/g,平均孔径增大近4倍,孔容减小.此外,ZnO-SiO2的孔径分布较窄,从1.7nm到15nm,而ZnOLa2O3-SiO2的孔径分布变宽,从1.7nm到90nm,大多数孔集中在15.56nm左右.通过XRD和XPS分析发现ZnO、La2O3和SiO2之间存在着较强的相互作用.

Effect of La2O3 on Structure Properties of ZnO-SiO2 Nanocomposites

Nanocomposites of ZnO-SiO 2 and ZnO-La 2O 3-SiO 2 have been prepared by sol-gel process. TEM photographs show that all of them are nano-meter sized particles; average particle diameters are 45nm and 35nm respectively. The specific surface area of ZnO-SiO 2 nanocomposite is 715.5m 2/g. The addition of La 2O 3 into ZnO-SiO 2 nanocomposite makes the specific surface area lessen sharply to 142.5m 2/g, the average pore size increase almost 4 times and the pore volume decrease. The pore diameter of ZnO-SiO 2 nanocomposite ranges from 1.7 nm to 15nm, while the pore size distribution of ZnO-La 2O 3-SiO 2 nanocomposite gets much wider, ranging from 1.7nm to 90nm, and most of the pores are around 15.56nm. XRD and XPS analyses prove that there are strong interactions among ZnO, La 2O 3 and SiO 2.