Interaction between NO x and the surface of supported heteropoly compounds: In situ IR spectroscopic data

Nitrate–nitrite equilibrium in the reaction of NO with a Cu-CHA catalyst for NH3-SCR

“…This is not straightforward, due to the low thermal stability of nitrite species, also in non-reactive atmospheres. [24][25][26] Recent studies on NO x storage reduction catalysts show that nitrite species react to form nitrates in the presence of NO x above 150 °C, 27 which complicates the detection of the Cu-nitrate/Cu-nitrite transformation. In NH 3 -SCR, this becomes less prominent due to the high reactivity of these species for NO and NH 3 in the SCR atmosphere.…”

“…Furthermore, complementary information is obtained from ultraviolet-visible-near infrared spectroscopy (UV-vis-NIR). [24][25][26]…”