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采用浸渍法制备了Ｌａ＿２Ｏ＿３、ＴｉＯ＿２、ＺｒＯ＿２以单层状态分散在ＳｉＯ＿２、Ａｌ＿２Ｏ＿３上的改性载体。用ＸＰＳ求得它们的最大单层分散阈值为：０．２２ｇＬａ＿２Ｏ＿３／１００ｍ￣２ＳｉＯ＿２，０．２７ｇＬａ＿２Ｏ＿３／１００ｍ￣２，０．０４ｇＴｉＯ＿２／１００ｍ￣２ＳｉＯ＿２，０．０３６ｇＴｉＯ＿２／１００ｍ￣２Ａｌ＿２Ｏ＿３，０．０７ｇＺｒＯ＿２／１００ｍ￣２ＳｉＯ＿２，０．０８ｇＺｒＯ＿２／１００ｍ￣２Ａｌ＿２Ｏ＿３。Ｌａ＿２Ｏ＿３可以完全铺满ＳｉＯ＿２、Ａｌ＿２Ｏ＿３载体表面，而ＴｉＯ＿２、ＺｒＯ＿２仅仅覆盖ＳｉＯ＿２（Ａｌ＿２Ｏ＿３）表面的４０％及５０％。在以涂层氧化物为载体的Ｐｄ催化剂制备过程中，通过ＸＰＳ的氩离子刻蚀技术，确定了Ｐｄ分布在以ＳｉＯ＿２（Ａｌ＿２Ｏ＿３）为骨架的涂层氧化物的表面上，与Ｌａ＿２Ｏ＿３、ＴｉＯ＿２、ＺｒＯ＿２在ＳｉＯ＿２（Ａｌ＿２Ｏ＿３）骨架上的分布基本一致，没有进入ＳｉＯ＿２（Ａｌ＿２Ｏ＿３）晶格内部。ＸＲＤ衍射图则说明在Ｐｄ催化剂配制过程中，ＴｉＯ＿２、ＺｒＯ＿２、Ｌａ＿２Ｏ＿３没有形成结晶相，也没有与ＳｉＯ＿２（Ａｌ＿２Ｏ＿３）发生反应，仍以单层分散形式存在?
La 2 O 3, TiO 2 and ZrO 2 were prepared by impregnation method. The modified supports were dispersed in SiO 2 and Al 2 O 3 on a single layer. The maximum monolayer dispersion thresholds obtained by XPS were 0.22gLa_2O_3 / 100m ~ 2SiO_2, 0.27gLa_2O_3 / 100m_2, 0.04gTiO_2 / 100m ~ 2SiO_2, 0.036gTiO_2 / 100m ~ 2Al_2O_3 and 0.07gZrO_2 / 100m ~ 2SiO_2, 0.08gZrO_2 / 100m ~ 2Al_2O_3. La 2 O 3 can completely cover the surface of SiO 2 and Al 2 O 3 supports, while TiO 2 and ZrO 2 only cover 40% and 50% of the surface of SiO 2 (Al 2 O 3). During the preparation of Pd catalyst with the oxide coating as carrier, Pd was deposited on the surface of SiO_2 (Al_2O_3) -coated oxide by XPS argon ion etching, and the results showed that Pd reacted with La_2O_3, TiO_2, The distribution of ZrO_2 on the SiO_2 (Al_2O_3) framework is basically the same and does not enter the interior of the SiO_2 (Al_2O_3) crystal lattice. XRD diffraction pattern shows that in the process of Pd catalyst preparation, TiO_2, ZrO_2 and La_2O_3 do not form crystalline phase, and do not react with SiO_2 (Al_2O_3).