Activity Trend for Low-Concentration NO Oxidation at Room Temperature on Rutile-Type Metal Oxides

The catalytic oxidation of low-concentration NO at room temperature has drawn increasing attention to eliminate NO in the large semiclosed spaces. However, the location of efficient catalysts is a challenging task. Herein, to rationalize the activity trend of NO oxidation and facilitate the catalyst screening/design, we computationally investigate the low-concentration NO oxidation processes on an important rutile-type of metal oxides (MO2, M = Mn, Ru, Ir, Rh) at room temperature. Some key scaling relations for the elementary steps following either the Mars–van Krevelen (MvK) mechanism or Langmuir–Hinshelwood (LH) mechanism, are revealed as a function of Ef(Ovac) (the formation energy of Obri vacancy) or Eads(O@M5c) (the adsorption energy of O at the metallic M5c site), and a 3D activity map following the MvK mechanism at room temperature is quantitatively constructed by combining the DFT results with microkinetic analyses. First, we identified the active region in terms of Ef(Ovac) and Eads(O@M5c) to obt...