Multifunctional hybrid materials are obtained by modifying zeolite L (ZL) with stopcock molecules, consisting of a tail group that can enter the ZL nanochannels and a head group too large to pass the channel opening. However, to date no microscopic-level structural information on modified ZL materials has been reported. Herein we draw atomistic pictures of channel openings and stopcock-functionalized ZL based on first-principles calculations. We elucidate the interactions of the tail group with the inner surface of ZL channels and the space-filling properties of the stopcocks, revealing cork- or lid-sealing modes. Water is essential to obtain stable modifications. AlOH groups are the preferred modification sites, bipodal modifications suffer from strain, and tripod binding is ruled out. Our results suggest the viability of recursive functionalization by cross-linking.
Keywords: density functional calculations; interfaces; nanostructures; supramolecular chemistry; zeolites.
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