Revealing the crystal facet effect on NO formation during the NH-SCR over α-MnO catalysts.

The detailed atomic-level mechanism of the effect induced by engineering the crystal facet of α-MnO catalysts on NO formation during ammonia-selective catalytic reduction (NH-SCR) was ascertained by combining density functional theory (DFT) calculations and thermodynamics/kinetic analysis. The surface energies of α-MnO with specific (100), (110), and (310) exposed planes were calculated, and the adsorptions of NH, NO, and O on three surfaces were analyzed. The adsorption energies showed that NH and NO molecules could be strongly adsorbed on the surface of the α-MnO catalyst, while the adsorption of O was weak.