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Manganese cobalt oxide catalystsprepared by the low-temperaturesolid phase reaction were modified by potassium-precursor promotersand used for the oxidation of nitric oxide at low temperature. Theactivity of modified catalysts had a significant improvement as follows:Mn–Co–KOH > Mn–Co–K2CO3> Mn–Co–KNO3, which was in goodagreement with the order of alkalinity. NH3/CO2-TPD results indicated that potassium-precursor promoters could regulatethe acid–basic and adsorption property of catalyst throughthe neutralization and intervention of K+/basic groups.The XRD, XPS, and NO-TPD results showed that the potassium precursorenhanced the dispersion, the ratios of Mn4+/Mn3+and Co2+/Co3+to some extent, especially forthe chemisorbed oxygen and adsorption performance of NO. The mainreasons of improvement may be attributed to the enhancement of NOadsorption performance and the synergetic effect between Co and Mnions. Finally, the possible reaction mechanisms are proposed. [ABSTRACT FROM AUTHOR]