Controlled Synthesis of Spinel-Type Mesoporous Mn–Co Rods for SCR of NO_<i>x</i> with NH₃ at Low Temperature

Abstract

In this work, a series of Mn–Co rod-like layered catalysts self-assembled from porous rod aggregates were fabricated by a simple solvothermal approach. Compared with Mn–Co particles, Mn–Co rods exhibited a much better SCR performance (achieving >93% NO x conversion at 75 °C) and high N 2 selectivity. The outstanding catalytic performance was mainly attributed to the large specific surface area and unique rod-like mesoporous structures, which could provide more active sites and reaction centers for the reaction gas to further promote the de-NO x performance of the catalyst. In addition, the high atomic ratio of Mn 4+ /Mn on the catalyst surface, strong acid strength, and large acidity amount also had positive effects on its catalytic activity. Moreover, Mn–Co rods possessed a better catalytic cycle performance and more surface acid sites due to the synergistic effect between Co and Mn species.