Noble Metal Particles Confined in Zeolites: Synthesis, Characterization, and Applications

Abstract

Noble metal nanoparticles or subnanometric particles confined in zeolites, that is, metal@zeolite, represent an important type of functional materials with typical core–shell structure. This type of material is known for decades and recently became a research hotspot due to their emerging applications in various fields. Remarkable achievements are made dealing with the synthesis, characterization, and applications of noble metal particles confined in zeolites. Here, the most representative research progress in metal@zeolites is briefly reviewed, aiming to boost further research on this topic. For the synthesis of metal@zeolites, various strategies, such as direct synthesis from inorganic or ligand‐assisted noble metal precursors, multistep postsynthesis encapsulation and ion‐exchange followed by reduction, are introduced and compared. For the characterization of metal@zeolites, several most useful techniques, such as electron microscopy, X‐ray based spectroscopy, infrared and fluorescence emission spectroscopy, are recommended to check the successful confinement of noble metal particles in zeolite matrix and their unique physiochemical properties. For the applications of metal@zeolites, catalysis and optics are involved with an emphasis on catalytic applications including the size‐dependent catalytic properties, the sintering‐resistance properties, the substrate shape‐selective catalysis, and catalysis modulation by zeolite microenvironment.

Graphene oxide and its derivatives as promising In-vitro bio-imaging platforms

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Characterization of Metal‐zeolite Composite Catalysts: Determining the Environment of the Active Phase

“…More recently, zeolite‐supported metallic catalysts, with nanoparticles encapsulated within the zeolite, have become a hot‐topic of research due to their advantages in shape‐selective reactions . The preparation methods of these catalysts can be divided into two groups: (1) direct synthesis, in which the metal species are encapsulated in situ, and (2) post‐synthesis, in which the metal particles are impregnated into a desilicated zeolite support .…”

“…Heterogeneous catalysts are often studied at high temperatures to initiate reactions. To identify trends in reduction, oxidation and adsorption of probe molecules, temperature programmed techniques are often employed . As demonstrated by Neylon et al.…”

Revival of Zeolite‐Templated Nanocarbon Materials: Recent Advances in Energy Storage and Conversion

“…recorded by IZA to date. [103][104][105] Herein, a brief introduction is provided from the following aspects of: i) structures, ii) Lewis acidity, and iii) ion-exchange capacity for ease of understanding the merits of zeolites as templates for synthesis of nanocarbons.…”

“…Zeolite molecular sieves, a family of aluminosilicates and their analogues, are crystalline, highly porous materials, which were originally observed in 1756 and 248 framework types have been recorded by IZA to date. [ 103–105 ] Herein, a brief introduction is provided from the following aspects of: i) structures, ii) Lewis acidity, and iii) ion‐exchange capacity for ease of understanding the merits of zeolites as templates for synthesis of nanocarbons.…”