Many zeolites are applied as industrial catalysts, with the choice of pore structures and catalytic site geometries allowing tuning of the catalytic properties. However, the narrowness of the pores may limit access of some reactants to the interior active sites. This limitation can be overcome by delamination of the zeolites to produce thin zeolitic sheets interspersed with meso-scale pores. ITQ-2 is a prototypical material in this class, but the high-pH medium needed for its synthesis produces unwanted partial amorphization of the zeolite layers [1]. In contrast, the exfoliation of MCM-22(P) has been demonstrated to occur at a pH that produces a less amorphized material, called UCB-1 [2]. Standard characterization techniques such as X-ray diffraction and nitrogen physisorption provide important information about the pore structures of these materials—but not at the nanoscale. Knowledge of the structure and morphology at the nanoscale—preferably in 3-D—is needed to guide the synthesis of improved delaminated zeolites.
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