NO Reduction on Cu‐Based Model Catalysts Studied by in‐situIRAS

Abstract

Cu-based catalyst has been widely used for catalytic reduction of NO. Well-defined TiO x /Cu(110) films were prepared and investigated by in situ reflection absorption infrared spectroscopy (IRAS), Auger electron spectroscopy (AES) and low energy electron diffraction (LEED). A complex surface structure of Cu + (-O-Ti-)-O-Cu + /Cu(110) was proposed, in which the topmost surface Cu + is highly dispersed, isolated and fixed by the TiO x layer. Such a 'single atom'-like surface site appears a very narrow  CO peak at 2130 cm -1 , and is more stable upon both CO reduction and vacuum annealing than the Cu 2 O/Cu(110). Such isolated Cu + (-O-Ti-) site on TiO x /Cu( 110) is also fairly stable in NO+CO reaction, but the overall catalytic activity is slightly lower than that on the Cu(110) surface, indicating that the single-atom Cu + (-O-Ti-) site is less efficient for NO+CO reaction at the examined conditions. The study provides useful information for the design and application of single-atom catalysts and understanding the nature of catalytically active centers.