% IMPORTANT: The following is UTF-8 encoded. This means that in the presence % of non-ASCII characters, it will not work with BibTeX 0.99 or older. % Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or % “biber”. @ARTICLE{Gashnikova:626128, author = {Gashnikova, Daria and Maurer, Florian and Bauer, Miriam R. and Bernart, Sarah and Jelic, Jelena and Lützen, Mads and Maliakkal, Carina B. and Dolcet, Paolo and Studt, Felix and Kübel, Christian and Damsgaard, Christian D. and Casapu, Maria and Grunwaldt, Jan-Dierk}, title = {{L}ifecycle of {P}d {C}lusters: {F}ollowing the {F}ormation and {E}volution of {A}ctive {P}d {C}lusters on {C}eria {D}uring {CO} {O}xidation by {I}n {S}itu/{O}perando {C}haracterization {T}echniques}, journal = {ACS catalysis}, volume = {14}, number = {19}, issn = {2155-5435}, address = {Washington, DC}, publisher = {ACS}, reportid = {PUBDB-2025-01319}, pages = {14871 - 14886}, year = {2024}, note = {(DFG) through grant no. INST 40/575-1 FUGG (JUSTUS2, RVs bw17D011).}, abstract = {For maximizing the atomic efficiency in noble metal-based catalysts, dedicated preparation routes and high lifetime are essential. Both aspects require an in-depth understanding of the fate of noble metal atoms under reaction conditions. For this purpose, we used a combination of complementary in situ/operando characterization techniques to follow the lifecycle of the Pd sites in a $0.5\%$ $Pd/5\%$ CeO2–Al2O3 catalyst during oxygen-rich CO oxidation. Time-resolved X-ray absorption spectroscopy showed that Pd cluster formation under reaction conditions is important for a high CO oxidation activity. In combination with density functional theory calculations, we concluded that the ideal Pd cluster size amounts to about 10–30 Pd atoms. The cluster formation and stability were affected by the applied temperature and reaction conditions. Already short pulses of 1000 ppm CO in the lean reaction feed were found to trigger sintering of Pd at temperatures below 200 °C, while at higher temperatures oxidation processes prevailed. Environmental transmission electron microscopy unraveled redispersion at higher temperatures (400–500 °C) in oxygen atmosphere, leading to the formation of single sites and thus the loss of activity. However, due to the reductive nature of CO, clusters formed again upon cooling in reaction atmosphere, thus closing the catalytic cycle. Exploiting the gained knowledge on the lifecycle of Pd clusters, we systematically investigated the effect of catalyst composition on the cluster formation tendency. As uncovered by DRIFTS measurements, the Pd to CeO2 ratio seems to be a key descriptor for Pd agglomeration under reaction conditions. While for higher Pd loadings, the probability of cluster formation increased, a higher CeO2 content leads to the formation of oxidized dispersed Pd species. According to our results, a Pd:CeO2 weight ratio of 1:10 for CeO2–Al2O3-supported catalysts leads to the highest CO oxidation activity under lean conditions independent of the applied synthesis method.}, cin = {FS DOOR-User}, ddc = {540}, cid = {$I:(DE-H253)FS_DOOR-User-20241023$}, pnm = {6G3 - PETRA III (DESY) (POF4-6G3) / SFB 1441 A03 - Reaktivität und hochentwickelte Elektronenmikroskopie von massenselektierten Clustern auf Oxidträgern (A03) (446697387) / SFB 1441 B01 - Synthese und Charakterisierung von Metalloxidträgern mit hoher Oberfläche (B01) (446700158) / SFB 1441 B02 - Systematische Synthese und katalytische Tests von definierten Edelmetallspezies auf Pulverträgern (B02) (446700275) / SFB 1441 B03 - In situ/operando-Charakterisierung von Edelmetallclustern und Partikeln auf Metalloxiden unter Reaktionsbedingungen (B03) (446701131) / SFB 1441 B04 - DFT-Gestützte Mikrokinetische Modellierung der Oxidativen Beseitigung von Schadstoffen (B04) (446701677) / DFG project G:(GEPRIS)460248799 - DAPHNE4NFDI - DAten aus PHoton- und Neutronen Experimenten für NFDI (460248799)}, pid = {G:(DE-HGF)POF4-6G3 / G:(GEPRIS)446697387 / G:(GEPRIS)446700158 / G:(GEPRIS)446700275 / G:(GEPRIS)446701131 / G:(GEPRIS)446701677 / G:(GEPRIS)460248799}, experiment = {EXP:(DE-H253)P-P65-20150101}, typ = {PUB:(DE-HGF)16}, UT = {WOS:001325925200001}, doi = {10.1021/acscatal.4c02077}, url = {https://bib-pubdb1.desy.de/record/626128}, }