Two-Dimensional Silica-Based Inorganic Networks

Abstract

Clay minerals, metal silicate hydrates, and zeolite precursors constitute a family of silicate-based layered materials with two-dimensional (2D) network structures. The present article provides the classification, identification, and structure determination of the main types of these materials. The natural occurrence of layered silicates as well as the approaches to their synthetic preparation is overviewed providing information about their availability, which is important because of valuable practical applications. The discussion of various structural transformations induced by intercalation or chemical processes summarizes well-known and recently developed approaches to the design and application of diverse layered derivatives based on clay minerals, metal silicate hydrates, and zeolite precursors. The characterization techniques that are crucial for determination of structural features and properties of lamellar silicate materials are also addressed. Overall, the aim of this article is to provide comprehensive overview of the state of the art of silicate-based layered materials, which are of great interest for both fundamental science and practical applications. The discussion emphasizes a novel seamless transition from 2D phyllosilicates to 3D frameworks (zeolites) enabled by the latter layered forms, which also introduce new types of transformations that were not possible or contemplated with the traditional layered structures.