The Crystal Chemistry and Topology of Modular Structures. III. 2D and 3D Zeolites Containing Tetrahedral Layers with the Apophyllite-Type Topology

Materials of the 2D zeolite class retain local catalytically active sites and the stability of traditional zeolites but with layered structures. Synthetic and naturally occurring single- and multilayer apophyllite-related compounds are prototypes of advanced industrial materials for use in various technologies. Their surface chemistry allows for functionalization, and these layers serve as fundamental building blocks for zeolitic frameworks. The discovery of the first triple-layer silicate, günterblassite, provided a critical link that established a fundamental crystal-chemical relationship between layered and framework structures in a wide range of micro- and mesoporous minerals and synthetic materials. The most prominent topic in the development of 2D zeolites remains the synthesis and structural characterization of these 2D zeolite structures This review offers a comprehensive overview of the current state of 2D and 3D zeolites constructed based on apophyllite-type layers. In accordance with the terms of modular crystal chemistry, we present a straightforward classification scheme based on the topological and symmetrical distinctions of the layers and provide ways for their stacking, creating a valuable basis for understanding the modular assembly of advanced porous materials.