以 Pd(C2 H3O2 ) 2 为前身 ,制备了系列 Ba O- Al2 O3复合氧化物负载钯的催化剂 .用质量滴定法 ,测定了复合载体的零电荷点 (pzc) .结果表明 ,体系的 pzc随 Ba O含量的增加而增大 ,在 5 %～ 10 %之间存在一拐点 ,并与XRD所测 Ba O在 Al2 O3上的单层分散阈值相对应 .复合载体在制备中发生固相反应 ,所生成的 Ba Al2 O4可以阻止 Al2 O3的相变 ,并极大地提高载体的热稳定性 ,其中 5 % Ba O的作用最为明显 .Ba O的引入 ,增强了 Pd/Al2 O3对 CO的氧化能力 ,同时 ,提高了其热稳定性 Pd (C2 H3O2) 2 was used as precursor to prepare a series of Ba O-Al 2 O 3 composite oxide supported palladium catalysts. The zero charge point (pzc) of the composite was measured by mass titration. The results showed that the pzc BaO content increases, and there is a inflexion point between 5% and 10%, which corresponds to the monolayer dispersion threshold of BaO on Al 2 O 3 as measured by XRD.The solid phase reaction occurred in the preparation of the composite support, The formed Ba Al 2 O 4 can prevent the phase transformation of Al 2 O 3 and greatly improve the thermal stability of the support, of which 5% Ba O plays the most significant role. The introduction of BaO enhanced the oxidation ability of Pd / Al 2 O 3 to CO , At the same time, improve its thermal stability