MnO x / CeO 2 catalysts for the low‐temperature selective catalytic reduction of NO with NH 3

CeO 2 –nanorod support was synthesized by hydrothermal method and different manganese oxides (MnO, MnO 2, and Mn 2 O 3 ) were impregnated over support by the wet‐impregnation forming MnO/CeO 2 ‐NR, MnO 2 /CeO 2 ‐NRm and Mn 2 O 3 /CeO 2 ‐NR. The physico‐chemical properties of the as‐prepared catalysts were analyzed using x‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area, x‐ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscope–energy‐dispersive x‐ray spectroscopy (SEM–EDX), hydrogen‐temperature‐programmed reduction (H 2 ‐TPR), and Raman spectroscopy. These catalysts were further analyzed for NO reduction using NH 3 as a reducing gas in the temperature range of 50 to 450°C. The results confirmed that MnO 2 /CeO 2 ‐NR gave the maximum NO conversion (65%) and N 2 selectivity (89%) among all catalysts. Further, MnO 2 /CeO 2 ‐NR catalyst was studied for the effect of MnO 2 loading and more than 90% NO conversion and N 2 selectivity were obtained in the temperature range of 250 to 300°C.