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Abstract Doping gold nanoparticles within covalent organic frameworks (AuNPs@COFs) has garnered enormous momentum due to their unique properties and broad applications. Nevertheless, prevailing multi‐step synthesis is plagued with low time efficiency, eco‐unfriendliness, and tedious protocols. Herein, we introduce a rapid, sustainable, scalable, one‐step mechanochemical strategy for synthesizing up to four AuNPs‐doped COFs via steel ball milling within an hour under ambient conditions. This approach overcomes the synthetic barriers of conventional multi‐step solution‐based methods, such as extended reaction times (5 days), milligram scale, the use of toxic solvents, elevated temperatures, and reliance on external reducing agents. One exemplary AuNPs@COF (AuNPs@DMTP‐TPB) exhibits high crystallinity, porosity, small AuNP size, and uniform dispersion (5.4±0.6 nm), surpassing its counterpart synthesized via multi‐step solution‐based methods (6.4±1.1 nm). Notably, the gram‐scale synthesis of AuNPs@DMTP‐TPB can be successfully achieved. Control experiments suggest that thein situformation of AuNPs is attributed to the galvanic reduction of gold precursor by stainless steel apparatus. As a proof‐of‐concept catalytic application, AuNPs@DMTP‐TPB demonstrates remarkable catalytic activity and recyclability for the aqueous reduction of 4‐nitrophenol under ambient conditions. This study provides an environmentally benign and fast pathway to synthesize AuNPs@COFs via mechanochemistry for the first time, opening tremendous possibilities for heterogeneous catalysis and beyond.
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A plasma‐based gas‐phase method for synthesis of gold nanoparticles
Abstract There are many applications for gold nanoparticles (AuNPs) due to their interesting optoelectronic properties such as tunable optical absorption and plasmonic resonance behavior. Although synthesis and stabilization of colloidal AuNPs are well established, new synthesis routes can lead to enhanced versatility of applications for AuNPs, particularly if the methods allow avoidance of solution processes or surfactants. Here, we introduce a plasma‐based synthesis of AuNPs, using a consumable gold wire and a radiofrequency power source. The AuNPs are monodisperse, with an average diameter of 4 nm. Although production yield is low, the narrow size distribution of the AuNPs and the avoidance of solution processing in this method are promising for future syntheses of metal NPs based on plasmas.
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- Award ID(s):
- 1651674
- PAR ID:
- 10101675
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Plasma Processes and Polymers
- Volume:
- 16
- Issue:
- 7
- ISSN:
- 1612-8850
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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