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CO的催化氧化不仅在环境保护方面有着重要的作用,同时也是催化研究中最常用的模型反应,如何制备高效的CO氧化催化剂是催化领域研究的热点之一.采用十六烷基三甲基溴化铵辅助-共沉淀法制备介孔Pd/Fe(OH)x催化剂,并研究不同温度焙烧对催化剂低温催化氧化CO性能的影响.通过N2低温吸附脱附,X射线衍射(XRD),H2-程序升温还原,透射电子显微镜(TEM),X射线能谱(XPS)等方法研究催化剂的结构与性能.研究发现,350℃焙烧得到催化剂的催化活性最佳,其中比表面积为199 m2·g-1,孔径为5.8 nm.催化剂Pd/Fe(OH)x能在-10℃实现CO完全转化.这是由于催化剂中贵金属Pd与载体Fe(OH)x强的相互作用使得部分载体与Pd共还原,从而使得催化剂表面具有较多的不饱和的Fe2+,促进了对氧的吸附和活化.即CO的吸附中心和氧活化中心分离,贵金属Pd作为CO的吸附中心,Fe(OH)x或者FeO x作为氧的活化中心,从而提高了催化剂的低温反应性能.“,”CO oxidation was studied widely not only because of its extensive application in environment protection and industrial pro -duction, but also as a model reaction for the catalytic study .Therefore it was considerably important to explore and design high efficien-cy catalyst for CO oxidation .Mesoporous Pd/Fe( OH) x was prepared by co-precipitation with trimethyl ammonium bromide for CO oxi-dation.The effects of calcination temperatures on structure and catalytic performance of the catalysts were investigated by nitrogen ad -sorption-desorption, X-ray diffraction ( XRD), H2 temperature programmed reduction ( H2-TPR), transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS).The experimental results revealed that mesoporous 1.1％Pd/Fe(OH)x calcinated at 350℃behaved the best performance in CO oxidation and 100％CO was converted at -10℃.The strong interaction between Pd and support led to the higher amount of Fe 3+involved in reduction .It led to the higher amount of Fe 2+on catalyst which promoted the adsorp-tion and activation of oxygen species , namely the separation of CO adsorption sites and oxygen sites .Pd and Fe(OH)x were used as the active site for CO adsorption and oxygen activation respectively which promoted CO oxidation at low temperature .