TY - JOUR
AU - Gashnikova, Daria
AU - Struzek, Samuel
AU - Maurer, Florian
AU - Bauer, Miriam R.
AU - Maliakkal, Carina B.
AU - Kübel, Christian
AU - Casapu, Maria
AU - Grunwaldt, Jan-Dierk
TI - Complementary and Spatially Resolved Operando Spectroscopic Investigation of Pt/Al<sub>2</sub>O<sub>3</sub> and Pt/CeO<sub>2</sub> Catalysts during CO/NO Conversion
JO - The journal of physical chemistry / C
VL - 129
IS - 31
SN - 1932-7447
CY - Washington, DC
PB - Soc.
M1 - PUBDB-2025-04555
SP - 13923 - 13938
PY - 2025
AB - The composition of reaction mixtures strongly influences the structural evolution and performance of noble metal-based catalysts. In this work, we compared the effect of the simultaneous presence of CO and NO on the noble metal state and CO oxidation activity of Pt/Al<sub>2</sub>O<sub>3</sub> and Pt/CeO<sub>2</sub> catalysts under close-to-stoichiometric conditions using complementary in situ/operando X-ray and infrared spectroscopic techniques. For the utilized catalysts, the integral catalytic performance data indicated a diminished CO oxidation activity in the presence of NO, which is due to a competitive adsorption of CO and NO, as elucidated by the diffuse reflectance infrared Fourier transform spectroscopy and high-energy resolution X-ray fluorescence X-ray absorption near-edge structure results. Spatially resolved operando X-ray absorption spectroscopy investigations and extended X-ray absorption fine structure analysis unraveled that the addition of NO led to a higher oxidation state of Pt along the entire catalyst bed for both samples. Moreover, NO was found to delay the reduction of Pt particles on Al<sub>2</sub>O<sub>3</sub> and hinder the formation of active Pt clusters on CeO<sub>2</sub>. As a result, a more oxidized Pt state at the beginning of the catalyst bed and a low overall activity were observed for Pt/CeO<sub>2</sub>. However, the CO oxidation activity could be enhanced by a reductive pretreatment of the Pt/CeO<sub>2</sub> catalyst, resulting in a similar reduced Pt state along the entire catalyst bed and minimizing the negative impact of NO during the combined reaction.
LB - PUB:(DE-HGF)16
DO - DOI:10.1021/acs.jpcc.5c01963
UR - https://bib-pubdb1.desy.de/record/639469
ER -