In Situ Time-Resolved Observation of the Development of Intracrystalline Mesoporosity in USY Zeolite
journal contributionposted on 02.12.2016, 00:00 by Noemi Linares, Alexander Sachse, Elena Serrano, Aida Grau-Atienza, Erika De Oliveira Jardim, Joaquín Silvestre-Albero, Marco Aurelio Liutheviciene Cordeiro, François Fauth, Garikoitz Beobide, Oscar Castillo, Javier García-Martínez
The development of intracrystalline mesoporosity within zeolites has been a long-standing goal in catalysis as it greatly contributes to alleviating the diffusion limitations of these widely used microporous materials. The combination of in situ synchrotron X-ray diffraction and liquid-cell transmission electron microscopy enabled the first in situ observation of the development of intracrystalline mesoporosity in zeolites and provided structural and kinetic information on the changes produced in zeolites to accommodate the mesoporosity. The interpretation of the time-resolved diffractograms together with computational simulations evidenced the formation of short-range hexagonally ordered mesoporosity within the zeolite framework, and the in situ electron microscopy studies allowed the direct observation of structural changes in the zeolite during the process. The evidence for the templating and protective role of the surfactant and the rearrangement of the zeolite crystal to accommodate intracrystalline mesoporosity opens new and exciting opportunities for the production of tailored hierarchical zeolites.