Juhyun Jeong  Subin Son  Seunghan Kim  Jinwoo Kim  Junsang Lee  Kyungmin Cho  Kanghee Cho  Jeong-Chul Kim

Vol. 31,  No. 1, pp. 1-15, Mar.  2025
10.7464/ksct.2025.31.1.1

Solid-state NMR Zeolites Catalysts Characterization Reaction mechanisms

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Zeolites are crystalline materials composed of silica and alumina linked by oxygen bridges. They exhibit a highly ordered pore structure that allows them to be applied in a variety of ways, including as acid/base catalysts (e.g., strong acid catalysts in heavy oil fluidized catalytic cracking), adsorbents (e.g., high-performance moisture adsorbents in dehydration processes), and cation exchange resins (e.g., water softeners). Considerable research has been devoted to developing new zeolite structures and compositions that enhance their performance across these applications. Macro-level analytical techniques such as nitrogen adsorption measurements, X-ray diffraction, and electron microscopy have been traditionally performed for zeolite material characterization. However, as energy efficiency and carbon footprint concerns escalate, the focus has shifted towards engineering novel zeolite materials that have precise surface properties in order to optimize their performance. This shift underscores the need for advanced analytical techniques for the molecular or atomic-level structural and physicochemical characterization of zeolites. Solid-state nuclear magnetic resonance (ssNMR) spectroscopy provides high-resolution information at the atomic scale, making it a valuable tool for this purpose. This review comprehensively examines the application of ssNMR techniques for analyzing zeolite materials within clean technology research and details fundamental principles and usage cases to demonstrate ssNMR’s relevance and utility in the field. In addition, this review summarizes previous research that has demonstrated how to characterize the structural and acidic properties of zeolites and how to reveal the detailed mechanisms of methanol-to-olefin and ethylene-to-propylene reactions.