caa a22 4500 47584467X CHVBK 20180406123910.0 cr unu---uuuuu 170329e20000301xx s 000 0 eng 10.1023/A:1019103815248 doi (NATIONALLICENCE)springer-10.1023/A:1019103815248 Platinum migration out of zeolites onto iron oxide: an alternative to H spillover [Elektronische Daten] [Hai‐Yang Liu, Wen‐An Chiou, Gerd Fröhlich, Wolfgang Sachtler] TPR shows that the reduction of Fe2O3 to Fe3O4 is strongly enhanced in mixtures with platinum‐containing mordenite. However, no hydrogen spillover takes place from Pt0 particles along the walls of the zeolite pores. Only migration of platinum out of the zeolite onto the Fe2O3 leads to enhanced reduction of Fe2O3. TEM and EDX prove unambiguously that Pt clusters decorate Fe2O3 particles after an oxidative pretreatment of intimate mixtures, followed by reduction. Two paths exist for this migration of oxidized platinum: as Pt2+ ions and as PtO or PtO2 clusters. The rate for both transport mechanisms increases with temperature. Pretreatment with H2O vapor results in hydrated ions which have higher mobility and lead to more homogeneous distribution of the platinum over iron oxide particles. Reduction in wet hydrogen is slower than in dry hydrogen; no reduction to Fe 0 occurs in wet hydrogen. Kluwer Academic Publishers, 2000 hydrogen spillover nationallicence oxide migration nationallicence enhanced reducibility nationallicence PtO2 migration through zeolite channels nationallicence effect of H2O on ion migration nationallicence ion migration nationallicence Liu Hai‐Yang V.N. Ipatieff Laboratory, Center for Catalysis and Surface Science, Department of Chemistry, Northwestern University, 60208, Evanston, IL, USA aut Chiou Wen‐An V.N. Ipatieff Laboratory, Center for Catalysis and Surface Science, Department of Chemistry, Northwestern University, 60208, Evanston, IL, USA aut Fröhlich Gerd V.N. Ipatieff Laboratory, Center for Catalysis and Surface Science, Department of Chemistry, Northwestern University, 60208, Evanston, IL, USA aut Sachtler Wolfgang V.N. Ipatieff Laboratory, Center for Catalysis and Surface Science, Department of Chemistry, Northwestern University, 60208, Evanston, IL, USA aut Topics in Catalysis Kluwer Academic Publishers-Plenum Publishers 10/1-2(2000-03-01), 49-57 1022-5528 10:1-2<49 2000 10 11244 https://doi.org/10.1023/A:1019103815248 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1019103815248 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Liu Hai‐Yang V.N. Ipatieff Laboratory, Center for Catalysis and Surface Science, Department of Chemistry, Northwestern University, 60208, Evanston, IL, USA aut NATIONALLICENCE 700 1- Chiou Wen‐An V.N. Ipatieff Laboratory, Center for Catalysis and Surface Science, Department of Chemistry, Northwestern University, 60208, Evanston, IL, USA aut NATIONALLICENCE 700 1- Fröhlich Gerd V.N. Ipatieff Laboratory, Center for Catalysis and Surface Science, Department of Chemistry, Northwestern University, 60208, Evanston, IL, USA aut NATIONALLICENCE 700 1- Sachtler Wolfgang V.N. Ipatieff Laboratory, Center for Catalysis and Surface Science, Department of Chemistry, Northwestern University, 60208, Evanston, IL, USA aut NATIONALLICENCE 773 0- Topics in Catalysis Kluwer Academic Publishers-Plenum Publishers 10/1-2(2000-03-01), 49-57 1022-5528 10:1-2<49 2000 10 11244 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer