A novel redox precipitation route was developed for the preparation of Ce-Mn composite oxides, where KMnO4 and Ce(NO3)(3) were adopted as precursors. The samples were tested for selective catalytic reduction (SCR) of NO by NH3 at low temperature, and characterized using X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), thermogravimetric analysis (TG), hydrogen temperature-programmed reduction (H-2-TPR), X-ray photoelectron spectroscopy (XPS) and in situ diffuse reflectance infrared transform spectroscopy (in situ DRIFT). This novel method produced samples with large specific surface area, low crystallinity, high oxidation degree and superior performances in low-temperature NH3-SCR. Ce-3Mn containing almost 100% Mn4+ ion on its surface exhibited superior low-temperature reducibility, reaching up to above 95% NO conversion almost throughout the entire testing range of 353-453 K. The surface concentration of Mn4+, the strong synergistic effects between MnO2 and CeO2-x and the large surface area played a key role for its excellent catalytic activity for the complete reduction of nitrogen oxides. A primary Eley-Rideal (E-R) reaction mechanism for Ce-3Mn catalyst was proposed with Lewis acid sites involved in the SCR reaction. (C) 2018 Published by Elsevier B.V.