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Copper containing catalyst were widespread using in many catalytic reaction,especially Cu-Zn mixed oxides,have been often studied in the partial oxidation for methanol (POM) reaction.POM,an exothermic reaction,has the advantage of being a quick initiation and no heat supply if the reaction reached steady-state,and is suitable to produce hydrogen for proton exchange membrane fuel cells (PEMFCs).Although,the Cu/ZnO catalysts displayed high catalytic activity at temperature c.a.200 oC,the worse CO selection also observed.Some authors [1,2] used precious metals,such as Au,to reduce the CO by-product and lower the reaction temperature,but price should be considered.It is well know that oxygen vacancies on the catalyst surface should improve the CO oxidation.Doping with transition metals [3,4] such as Zr and Ce,would generate native defects (oxygen vacancies),but sometimes the overall catalytic activity would sacrifice.Y.G.Lin et al.[5] used the CuO-ZnO inverse opals to generate oxygen vacancies by O2-plasma treatment and promote the performance of methanol microreformer efficiency,but the preparation process of catalysts isnt common.In our study,we proposed a new simple and very cheap method to generate oxygen vacancies on the surface of the Cu/ZnO catalyst by deposited precipitation method.As the results of the PL spectrum,a peak near 510 nm could be associated green emission by singly ionized oxygen vacancies in ZnO.From the XRD and TEM data,the particle size is approximately 19 nm.In addition,the conversion of methanol can be promoted effectively and the amount of CO is not detected at each temperature by loading micro-channel reactor with Cu/vacancy ZnO.