The zeolites, a class of materials with uniform porosity, high crystallinity, structural diversity, and large surface area, have been extensively studied in both synthesis and applications in catalysis, separation, and adsorption. In the zeolite crystals, the uniform nanopores benefit molecular diffusion, but the absence of catalytically active metal species (e.g. isolated metal site, nanocluster, and nanoparticle) strongly limits their wide applications. Solution to this problem is to fix the active sites inside of the nanoporous crystals. In this review, it is briefly summarized recent developments on metal-based active species fixed in zeolite crystals, including the synthesis strategies, catalytic performances, and mechanism investigations. It is emphasized that the nanoparticles of metals and metal oxides fixed inside of zeolite crystals effectively combine the advantages of high activity of the nanoparticles and the selectivity/stability of the zeolite, resulting in enhanced catalytic performances in a series of reactions. Particularly, the metal nanoparticles are effectively stabilized by the zeolite sheath, giving superior sinter resistance at harsh reaction conditions.

沸石是具有均匀孔隙率，高结晶度，结构多样性和大表面积的一类材料，已经在合成，催化，分离和吸附方面进行了广泛的研究。在沸石晶体中，均匀的纳米孔有利于分子扩散，但没有催化活性金属物质（例如分离的金属位点，纳米簇和纳米颗粒）强烈限制了它们的广泛应用。解决该问题的方法是将纳米孔晶体内部的活性位点固定。在这篇综述中，它简要概述了固定在沸石晶体中的金属基活性物质的最新进展，包括合成策略，催化性能和机理研究。要强调的是，固定在沸石晶体内部的金属和金属氧化物的纳米颗粒有效地结合了纳米颗粒的高活性和沸石的选择性/稳定性的优点，从而导致在一系列反应中增强的催化性能。特别地，金属纳米颗粒被沸石护套有效地稳定，从而在苛刻的反应条件下具有优异的耐烧结性。