Hierarchical Zeolites: Synthesis Strategies, Crystallization Mechanisms, and Machine Learning

The revelation of the crystallization mechanism of zeolites is the key to shifting their synthesis from trial-and-error methods to predictive approaches. This review introduces the traditional and recently emerging green synthesis methods of hierarchical zeolites and compares their crystallization mechanisms from the perspective of synthesis strategies. Then, by discussing the classical and nonclassical theories, it analyzes the crystallization mechanisms of different synthesis strategies for hierarchical zeolites and finds that the research on kinetic control methods not only conforms to the theme of green and environmentally friendly synthesis at present but also can further explore the mechanism of zeolite crystallization. Finally, this review also presents the research results of the emerging machine learning-assisted zeolite structure design, which will bring new possibilities for the future realization of hierarchical zeolite structure design and directed synthesis through predictive methods.