Effect of Al-distribution on oxygen activation over Cu-CHA
Artikel i vetenskaplig tidskrift, 2018

Cu(NH 3 ) 2 + -pairs in chabazite (CHA) have been suggested to activate oxygen during lowerature selective catalytic reduction of nitrogen oxides with ammonia (NH 3 -SCR). As charge neutrality requires that each Cu-complex is associated with a framework Al, the Al-distribution may affect Cu(NH 3 ) 2 + -pair formation and subsequent oxygen activation. Here, density functional theory calculations in combination with ab initio molecular dynamics simulations are used to explore Cu(NH 3 ) 2 + -pair formation and oxygen activation in Cu-CHA. The Al-distribution is found to markedly affect the probability for Cu(NH 3 ) 2 + -pair formation. Moreover, the molecular dynamics simulations reveal a low-energy reaction path for O 2 activation and dissociation. The facile O 2 dissociation suggests that Cu-pair formation rather than O 2 activation governs the lowerature NH 3 -SCR activity. The results indicate that precise synthesis of Cu-exchanged chabazite with respect to Al-distribution may enhance the catalytic activity.

Författare

Lin Chen

Chalmers, Fysik, Kemisk fysik

Kompetenscentrum katalys (KCK)

Hanne Falsig

Haldor Topsoe

Ton Janssens

Haldor Topsoe

Jonas Jansson

Volvo Group

Magnus Skoglundh

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Polymerteknologi

Kompetenscentrum katalys (KCK)

Henrik Grönbeck

Kompetenscentrum katalys (KCK)

Chalmers, Fysik, Kemisk fysik

Catalysis Science and Technology

2044-4753 (ISSN) 2044-4761 (eISSN)

Vol. 8 8 2131-2136

Ämneskategorier

Oorganisk kemi

Teoretisk kemi

Organisk kemi

DOI

10.1039/c8cy00083b

Mer information

Senast uppdaterat

2018-05-28