Get access

Relevance of the Nitrite Route in the NOx Adsorption Mechanism over Pt–Ba/Al2O3 NOx Storage Reduction Catalysts Investigated by using Operando FTIR Spectroscopy

Authors

  • Prof.  L. Lietti,

    Corresponding author
    1. Dipartimento di Energia, Laboratory of Catalysis and Catalytic Processes and NEMAS, Centre of Excellence Politecnico di Milano, P.zza L. Da Vinci 32, 20133 Milano (Italy), Fax: (+39) 02-2399-3318
    • Dipartimento di Energia, Laboratory of Catalysis and Catalytic Processes and NEMAS, Centre of Excellence Politecnico di Milano, P.zza L. Da Vinci 32, 20133 Milano (Italy), Fax: (+39) 02-2399-3318
    Search for more papers by this author
  • Prof.  M. Daturi,

    1. Laboratoire Catalyse et Spectrochimie, ENSICAEN, Université de Caen, CNRS, 6 Bd Maréchal Juin, F-14050 Caen (France)
    Search for more papers by this author
  • Dr.  V. Blasin-Aubé,

    1. Laboratoire Catalyse et Spectrochimie, ENSICAEN, Université de Caen, CNRS, 6 Bd Maréchal Juin, F-14050 Caen (France)
    Search for more papers by this author
  • Prof.  G. Ghiotti,

    1. Dipartimento di Chimica IFM, NIS Centre of Excellence, Università di Torino via P. Giuria 7, 10125 Torino (Italy)
    Search for more papers by this author
  • Dr.  F. Prinetto,

    1. Dipartimento di Chimica IFM, NIS Centre of Excellence, Università di Torino via P. Giuria 7, 10125 Torino (Italy)
    Search for more papers by this author
  • Prof.  P. Forzatti

    1. Dipartimento di Energia, Laboratory of Catalysis and Catalytic Processes and NEMAS, Centre of Excellence Politecnico di Milano, P.zza L. Da Vinci 32, 20133 Milano (Italy), Fax: (+39) 02-2399-3318
    Search for more papers by this author

Abstract

original image

Nitrites dominate! Nitrites and nitrates are formed on the catalyst surface upon storage of NOx over a model Pt–Ba/Al2O3 NOx storage–reduction catalyst. Nitrites are formed through the oxidation of NO at the Pt–Ba interface (nitrite route), while nitrates are formed upon nitrite oxidation and/or NO2 adsorption following NO oxidation at Pt sites. The nitrite route is the unique pathway responsible for the storage of NOx at low temperatures, but it also dominates at high temperatures.

Ancillary