LAUSR

Hierarchical porous zeolites attract great attention because of their porosity on different scales to improve molecular diffusion. Here, we report mesoporous Faujasite (FAU) zeolite nanosheets with intergrown structure synthesized in an additive-free system. The sample was composed of uniform nanosheets with a slice thickness of ∼50 nm, which held a honeycomb-like structure with abundant mesopores. This material exhibits both microporous and mesoporous structure: the intrinsic micropores with a diameter about 0.74 nm in the zeolite framework and the mesopores with a diameter about 10 nm existing within the zeolite nanosheets. The Si/Al ratios can be adjusted from 1.1 to 1.9 (zeolites X or Y). In addition, this simple and environmental method may provide inspiration to the synthesis of other hierarchical zeolites.摘要本文用无添加剂体系合成了具有共生结构的介孔FAU沸石. 该材料具有由约50纳米厚度的纳米片堆积形成的花状形貌, 而且具有两种孔道体系: 沸石骨架本身的微孔和存在于纳米片内部的晶间介孔. 通过对合成条件精确的控制以及对反应物比例的筛选, 分别合成了介孔X(硅铝比<1.5)型和Y(硅铝比>1.5)型沸石. 温和的温度以及高碱度使得在成核初期发生结晶-溶解-重结晶过程是形成介孔FAU沸石的关键条件. 该合成体系用简单和低成本的方法在FAU沸石中引入介孔, 有望突破沸石在大分子催化中的限制, 将有可能应用于工业化生产.