TY - JOUR

T1 - Dynamics of Pd Dopant Atoms inside Au Nanoclusters during Catalytic CO Oxidation

AU - García, Clara

AU - Truttmann, Vera

AU - Lopez, Irene

AU - Haunold, Thomas

AU - Marini, Carlo

AU - Rameshan, Christoph

AU - Pittenauer, Ernst

AU - Kregsamer, Peter

AU - Dobrezberger, Klaus

AU - Stöger-Pollach, Michael

AU - Barrabés, Noelia

AU - Rupprechter, Günther

N1 - Publisher Copyright: © 2020 American Chemical Society.

PY - 2020/10/20

Y1 - 2020/10/20

N2 - Doping gold nanoclusters with palladium has been reported to increase their catalytic activity and stability. PdAu24 nanoclusters, with the Pd dopant atom located at the center of the Au cluster core, were supported on titania and applied in catalytic CO oxidation, showing significantly higher activity than supported monometallic Au25 nanoclusters. After pretreatment, operando DRIFTS spectroscopy detected CO adsorbed on Pd during CO oxidation, indicating migration of the Pd dopant atom from the Au cluster core to the cluster surface. Increasing the number of Pd dopant atoms in the Au structure led to incorporation of Pd mostly in the S-(M-S)n protecting staples, as evidenced by in situ XAFS. A combination of oxidative and reductive thermal pretreatment resulted in the formation of isolated Pd surface sites within the Au surface. The combined analysis of in situ XAFS, operando DRIFTS, and ex situ XPS thus revealed the structural evolution of bimetallic PdAu nanoclusters, yielding a Pd single-site catalyst of 2.7 nm average particle size with improved CO oxidation activity.

AB - Doping gold nanoclusters with palladium has been reported to increase their catalytic activity and stability. PdAu24 nanoclusters, with the Pd dopant atom located at the center of the Au cluster core, were supported on titania and applied in catalytic CO oxidation, showing significantly higher activity than supported monometallic Au25 nanoclusters. After pretreatment, operando DRIFTS spectroscopy detected CO adsorbed on Pd during CO oxidation, indicating migration of the Pd dopant atom from the Au cluster core to the cluster surface. Increasing the number of Pd dopant atoms in the Au structure led to incorporation of Pd mostly in the S-(M-S)n protecting staples, as evidenced by in situ XAFS. A combination of oxidative and reductive thermal pretreatment resulted in the formation of isolated Pd surface sites within the Au surface. The combined analysis of in situ XAFS, operando DRIFTS, and ex situ XPS thus revealed the structural evolution of bimetallic PdAu nanoclusters, yielding a Pd single-site catalyst of 2.7 nm average particle size with improved CO oxidation activity.

UR - http://www.scopus.com/inward/record.url?scp=85096060229&partnerID=8YFLogxK

U2 - 10.1021/acs.jpcc.0c05735

DO - 10.1021/acs.jpcc.0c05735

M3 - Article

AN - SCOPUS:85096060229

VL - 124.2020

SP - 23626

EP - 23636

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 43

ER -