Hierarchical two-dimensional (2D) lamellar zeolites represent a young emerging field and a novel expression of the zeolite frameworks. Accompanied with synthesis and catalytic performance investigation, assessment on the local environment and catalytic behavior of acid sites in 2D zeolites are needed. Here, we described the local environment of Lewis acid sites and evaluated catalytic activities of external acid sites (i.e. sites on external surface and in mesopores) in 2D lamellar titanium silicalite-1 (TS-1) zeolites. For comparison purpose, four TS-1 zeolites, including 3D TS-1, multilamellar 2D TS-1 without pillarization and with pillarization by silica and silica/titania, respectively, were prepared. The local environment of Ti-sites, including coordination status of Ti-atom, speciation of hydroxyl (-OH) group that hints degree of confinement, acid site strength and accessibility, was collectively assessed by spectroscopic and organic base titration measurements. Kinetic studies of cyclooctene (C₈H₁₄) epoxidation with hydrogen peroxide (H₂O₂) discerned catalytic activity of external Ti-sites that decreased with increasing mesoporosity due to decrease in site confinement.

层状二维（2D）层状沸石代表了一个新兴领域和一种新颖的沸石骨架表达形式。伴随着合成和催化性能研究，需要评估局部环境和二维沸石中酸性位点的催化行为。在这里，我们描述了路易斯酸性位点的局部环境，并评估了二维片状钛硅沸石1（TS-1）沸石中外部酸性位点（即外部表面和中孔中的位点）的催化活性。为了比较目的，制备了四种TS-1沸石，分别包括没有柱化和具有被二氧化硅和二氧化硅/二氧化钛柱化的3D TS-1，多层2D TS-1。Ti位点的局部环境，包括Ti原子的配位状态，暗示（-OH）限制程度的羟基（-OH）的形态，酸位点强度和可及性，通过光谱法和有机碱滴定法共同评估。环辛烯（C₈ H ₁₄）用过氧化氢（H ₂ O ₂）环氧化发现外部Ti-位的催化活性随位孔限制的降低而随介孔率的增加而降低。