Sm-MnOx/TiO2-{001} with preferentially exposed anatase {001} facet for selective catalytic reduction of NO with NH3

TiO2-{001} with preferentially exposed {001} supported SmMnOx was prepared for NOx reduction with NH3. The optimal TiMn30Sm10-{001} demonstrated remarkable low temperature catalytic activity (T50 % = 71 C). Besides, TiMn30Sm10-{001} achieved 80 % NO conversion under a wide temperature window (140-280 C) under gas hourly space velocity (GHSV) of 50000 h-1, along with excellent catalytic stability (> 85 % NO conversion for 24 h at 200 C) in both dry and humid conditions. It also showed enhanced N2 selectivity with T80 % range from 60 to 160 C. The outstanding catalytic performance of TiMn30Sm10-{001} was attributed to the combined efforts of high concentration of Mn3+, abundant surface adsorbed oxygen, and more acid sites due to the addition of SmOx and facets effect of TiO2-{001}. In situ infrared fourier transform spectroscopy analysis revealed that the NO reduction over TiMn30Sm10-{001} obeyed Langmuir-Hinshelwood mechanism. This work provides a rational strategy for designing facet-engineered catalysts for low-temperature SCR.