Department of Chemical Engineering and Materials Science, University of Minnesota, 151 Amundson Hall, 421 Washington Avenue Southeast, Minneapolis, MN 55455, USA.
Science. 2011 Oct 7;334(6052):72-5. doi: 10.1126/science.1208891.
Thin zeolite films are attractive for a wide range of applications, including molecular sieve membranes, catalytic membrane reactors, permeation barriers, and low-dielectric-constant materials. Synthesis of thin zeolite films using high-aspect-ratio zeolite nanosheets is desirable because of the packing and processing advantages of the nanosheets over isotropic zeolite nanoparticles. Attempts to obtain a dispersed suspension of zeolite nanosheets via exfoliation of their lamellar precursors have been hampered because of their structure deterioration and morphological damage (fragmentation, curling, and aggregation). We demonstrated the synthesis and structure determination of highly crystalline nanosheets of zeolite frameworks MWW and MFI. The purity and morphological integrity of these nanosheets allow them to pack well on porous supports, facilitating the fabrication of molecular sieve membranes.
薄沸石膜在分子筛膜、催化膜反应器、渗透屏障和低介电常数材料等诸多领域都具有广泛的应用前景。高纵横比沸石纳米片在组装和加工方面具有优势，因此使用高纵横比沸石纳米片合成薄沸石膜是很有吸引力的。然而，由于其层状前体结构的劣化和形态的破坏（如碎片化、卷曲和聚集），通过剥离层状前体来获得沸石纳米片的分散悬浮液的尝试受到了阻碍。我们成功地合成并确定了具有高结晶度的 MWW 和 MFI 沸石骨架纳米片的结构。这些纳米片的纯度和形态完整性使其能够很好地在多孔载体上组装，从而有利于分子筛膜的制备。
