Samenvatting
Incorporation of germanium in zeolites is well known to confer static flexibility to their framework, by stabilizing the formation of small rings. In this work, we show that the flexibility associated to Ge atoms in zeolites goes beyond this static effect, manifesting also a clear dynamic nature, in the sense that it leads to enhanced molecular diffusion. Our study combines experimental and theoretical methods providing evidence for this effect, which has not been described previously, as well as a rationalization for it, based on atomistic grounds. We have used both pure-silica and silico-germanate ITQ-29 (LTA topology) zeolites as a case study. Based on our simulations, we identify the flexibility associated to the pore breathing-like behavior induced by the Ge atoms, as the key factor leading to the enhanced diffusion observed experimentally in Ge-containing zeolites.
| Originele taal-2 | Engels |
|---|---|
| Pagina's (van-tot) | 10036-10043 |
| Aantal pagina's | 8 |
| Tijdschrift | Chemistry : A European Journal |
| Volume | 22 |
| Nummer van het tijdschrift | 29 |
| DOI's | |
| Status | Gepubliceerd - 11 jul. 2016 |
| Extern gepubliceerd | Ja |
Financiering
We thank the contribution from the European Research Council through an ERC Starting Grant (ERC2011-StG-279520-RASPA), the MINECO (CTQ2013-48396-P), the Andaluc?a Region (FQM-1851) and the Royal Society (International Exchange Scheme grant REA004). We thank Centro Informatico Cientifico de Andalucia (CICA) for providing computing resources. M.P., F.R. and S.V. thank the financial support by the Spanish Government (MAT2015-71842-P, Consolider Ingenio 2010-Multicat CSD-2009-00050 and Severo Ochoa SEV-2012-0267).