Zeitschriftenartikel:
Z. Jakub, J. Hulva, M. Meier, R. Bliem, F. Kraushofer, M. Setvin, M. Schmid, U. Diebold, C. Franchini, G. Parkinson:
"Local Structure and Coordination Define Adsorption in a Model Ir1/Fe3O4 Single-Atom Catalyst";
Angewandte Chemie International Edition,
58
(2019),
S. 13961
- 13968.
Kurzfassung englisch:
Single-atomcatalysts(SACs)bridgehomo-andheterogeneouscatalysisbecausethe activesite is ametal atomcoordinatedto surfaceligands.The localbindingenvironmentof the atomshouldthusstronglyinfluencehowreactantsadsorb.Now,atomicallyresolvedscanning-probemicroscopy,X-rayphotoelectronspectroscopy, temperature-programmeddesorption,andDFTare usedto studyhowCObindsatdifferentIr1siteson apreciselydefinedFe3O4(001)support.The two-and five-fold-coordinatedIr adatomsbindCO morestronglythanmetallicIr,and adoptstructuresconsistentwithsquare-planarIrIand octahedralIrIIIcomplexes,respectively.Ir incorporatesinto the subsurfacealreadyat 450 K, becominginactivefor adsorption.Above 900 K, the Ir adatomsagglom-erateto formnanoparticlesencapsulatedby ironoxide.TheseresultsdemonstratethelinkbetweenSACsystemsandcoordinationcomplexes,and thatincorporationintothesupportis an importantdeactivationmechanism.
Schlagworte:
10.1002/ange.2019
Erstellt aus der Publikationsdatenbank der Technischen Universität Wien.