Detection of key transient Cu intermediates in SSZ-13 during NH&lt;sub&gt;3&lt;/sub&gt;-SCR deNO&lt;em&gt;&lt;sub&gt;x&lt;/sub&gt;&lt;/em&gt; by modulation excitation IR spectroscopy

Greenaway, Alex G.; Marberger, Adrian; Thetford, Adam; Lezcano-González, Inés; Agote-Arán, Miren; Nachtegaal, Maarten; Ferri, Davide; Kröcher, Oliver; Catlow, C. Richard A.; Beale, Andrew M.

doi:10.1039/C9SC04905C

Detection of key transient Cu intermediates in SSZ-13 during NH₃-SCR deNO_x by modulation excitation IR spectroscopy

Greenaway AG, Marberger A, Thetford A, Lezcano-González I, Agote-Arán M, Nachtegaal M, Ferri D, Kröcher O, Catlow CRA & Beale AM

Citation

Greenaway, A. G., Marberger, A., Thetford, A., Lezcano-González, I., Agote-Arán, M., Nachtegaal, M., … Beale, A. M. (2020). Detection of key transient Cu intermediates in SSZ-13 during NH₃-SCR deNO_x by modulation excitation IR spectroscopy. Chemical Science, 11(2), 447-455. https://doi.org/10.1039/C9SC04905C

Persistent URL https://www.dora.lib4ri.ch/psi/islandora/object/psi:28144

The small pore zeolite Cu-SSZ-13 is an efficient material for the standard selective catalytic reduction of nitrogen oxides (NO_x) by ammonia (NH₃). In this work, Cu-SSZ-13 has been studied at 250 °C under high conversion using a modulation excitation approach and analysed with phase sensitive detection (PSD). While the complementary X-ray absorption near edge structure (XANES) spectroscopy measurements showed that the experiments were performed under cyclic Cu⁺/Cu²⁺ redox, Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) experiments provide spectroscopic evidence for previously postulated intermediates Cu–N(=O)–NH₂ and Cu–NO₃ in the NH₃-SCR deNO_x mechanism and for the role of [Cu²⁺(OH⁻)]⁺. These results therefore help in building towards a more comprehensive understanding of the reaction mechanism which to date has only been postulated in silico.