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The preparation of ultra–small silver nanoparticles (average diameter ≤10 nm) is a technical problem because of their aggregation tendency. Therefore, the preparation conditions are usually harsh and complex. It is widely recognized that covalent organic frameworks (COFs) represent a novel class of porous crystalline compounds with broad applications in various fields. In this work, an environmentally and economically friendly new method has been developed for synthesizing ultra–small silver nanoparticles by reducing silver ions in ethanol solution with a covalent organic framework (TPB–DMTP–COF) as a template and reductant at room temperature. Interestingly, the TPB–DMTP–COF not only serves as a template and reductant but also functions as a stabilizer. Moreover, the TPB–DMTP–COF can be utilized repeatedly as a reductant. The morphology and structure of the silver nanoparticles were examined using transmission electron microscopy and showed that they were spherical with an average particle size of approximately 7.5 nm. Compared with the previously reported silver nanoparticles, the silver nanoparticles synthesized by this new method are not coated with Surfactant, such as Polyvinylpyrrolidone (PVP). As a result, they possess a larger exposed surface area, exhibit increased activity, and demonstrate excellent antimicrobial properties against both Gram–negative Escherichia coli and Gram–positive bacteria Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Ag+ exchanged zeolites (Ag-zeolites) combining the advantages of high stability of microporous zeolites with the unique optical properties of silver clusters are attractive as promising functional materials. In this work, we systematically studied the optical properties of Ag+ exchanged SOD zeolites, obtaining tuned emission from yellow to blue and for the first time acquired white-emitting Ag-zeolite phosphors at a mild temperature (<300 °C). This tunable emission color was found to be caused by lattice shrinkage and lattice expansion of the framework in SOD zeolites. The obtained white emitting phosphors show Commission Internationale de I'Eclairage (CIE) chromaticity coordinates of (0.33, 0.34) under 395 nm excitation. In addition, we fabricated warm white LEDs with these white emitting phosphors, which show CIE coordinates of (0.37, 0.34), with a lower correlated color temperature (CCT) of 4329 K and a higher color rendering index (CRI) of 91. [ABSTRACT FROM AUTHOR]

Ag+ exchanged zeolites (Ag-zeolites) combining the advantages of high stability of microporous zeolites with the unique optical properties of silver clusters are attractive as promising functional materials. In this work, we systematically studied the optical properties of Ag+ exchanged SOD zeolites, obtaining tuned emission from yellow to blue and for the first time acquired white-emitting Ag-zeolite phosphors at a mild temperature (<300 °C). This tunable emission color was found to be caused by lattice shrinkage and lattice expansion of the framework in SOD zeolites. The obtained white emitting phosphors show Commission Internationale de I'Eclairage (CIE) chromaticity coordinates of (0.33, 0.34) under 395 nm excitation. In addition, we fabricated warm white LEDs with these white emitting phosphors, which show CIE coordinates of (0.37, 0.34), with a lower correlated color temperature (CCT) of 4329 K and a higher color rendering index (CRI) of 91.