Artigo Acesso aberto Revisado por pares

Resolving Interparticle Heterogeneities in Composition and Hydrogenation Performance between Individual Supported Silver on Silica Catalysts

2015; American Chemical Society; Volume: 5; Issue: 11 Linguagem: Inglês

10.1021/acscatal.5b02119

ISSN

2155-5435

Autores

Eva Plessers, Ivo Stassen, Sreeprasanth Pulinthanathu Sree, Kris P. F. Janssen, Haifeng Yuan, Johan A. Martens, Johan Hofkens, Dirk De Vos, Maarten B. J. Roeffaers,

Tópico(s)

Nanocluster Synthesis and Applications

Resumo

Supported metal nanoparticle catalysts are commonly obtained through deposition of metal precursors onto the support using incipient wetness impregnation. Typically, empirical relations between metal nanoparticle structure and catalytic performance are inferred from ensemble averaged data in combination with high-resolution electron microscopy. This approach clearly underestimates the importance of heterogeneities present in a supported metal catalyst batch. Here we show for the first time how incipient wetness impregnation leads to 10-fold variations in silver loading between individual submillimeter-sized silica support granules. This heterogeneity has a profound impact on the catalytic performance, with 100-fold variations in hydrogenation performance at the same level. In a straightforward fashion, optical microscopy interlinks single support particle level catalytic measurements to structural and compositional information. These detailed correlations reveal the optimal silver loading. A thorough consideration of catalyst heterogeneity and the impact thereof on the catalytic performance is indispensable in the development of catalysts.

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