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Effectively controlling the release behavior of silver bactericide to promote its antibacterial ability is highly important in the fields of chemical, biomedical and biotechnology industry. In this study, ultrasmall Ag clusters were successfully encapsulated into silicalite-1 zeolite through in situ hydrothermal approach, and the key to this success was choosing 3-mercaptopropyltriethoxysilane as ligand to facilitate Ag precursor involved into zeolite initial sol-gel system. The structure of prepared silicalite-1 zeolite encapsulation of Ag clusters (denoted as Ag@Silicalite-1) has been well defined with various characterizations and probe reactions. Benefiting from confinement effect and shape-selectivity of silicalite-1 zeolite, Ag@Silicalite-1 sample showed much better Ag+ controlled release performance than that of sample with Ag nanoparticles impregnated onto silicalite-1 zeolite (denoted as Ag/Silicalite-1). The release behavior of Ag+ in Ag@Silicalite-1 can be well described with ritger-peppas model. Taking killing Escherichia coli as an example, in comparison with Ag/Silicalite-1, Ag@Silicalite-1 sample displayed more efficient and sustainable antibacterial activity for its controlled release character. [Display omitted] • Ultrasmall Ag clusters were successfully in situ encapsulated into silicalite-1 zeolite. • Encapsulated Ag clusters displayed interesting controlled release behavior and well anti-poisoning property. • Silicalite-1 encapsulated Ag clusters showed sustainable and efficient antibacterial activity. [ABSTRACT FROM AUTHOR]

It is challenging to establish single metal atoms with a uniform coordination environment at targeted sites of a zeolite. In this study, single platinum atoms were selectively encaged in the six-membered rings of sodalite (SOD) cages within Y zeolite using a template-guiding strategy. During the in situ synthesis process, template molecules were designed to occupy supercages and thereby force coordinated platinum species into SOD cages. Subsequent control of the post-treatment conditions yielded the Y zeolite with selectively encaged single platinum atoms, denoted Pt@Y-SOD. The Pt@Y-SOD catalyst had good stability and excellent catalytic selectivity in the semihydrogenation reaction, and it exhibited interesting thiophene and carbon monoxide resistance in this transformation because interactions with these poisons are weakened by the configuration of the encaged single platinum atoms., (© 2022 Wiley-VCH GmbH.)