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Abstract The rapid and environmentally benign synthesis of metal‐immobilized covalent organic frameworks (metal/COFs) for heterogeneous catalysis is a pervasive challenge, as the mainstream synthesis is exceedingly time‐consuming (up to four days) and demands the use of hazardous solvents. Herein, we describe a sustainable and efficient one‐step sonochemical strategy for constructing diverse palladium (II)‐immobilized COFs (Pd(II)/COFs). By merging the sonochemistry‐assisted COF synthesis and in situ Pd (II) immobilization into a single step, this strategy enables the rapid formation of Pd(II)/COF hybrids within an hour under ambient conditions using water as the solvent. Notably, gram‐scale synthesis of Pd(II)/COFs is achievable. The resulting Pd(II)/COFs exhibit superb crystallinity and high surface area, leading to remarkable activity, excellent functionality tolerance, and high recyclability for the Suzuki–Miyaura cross‐coupling reaction of aryl bromides and arylboronic acids at room temperature. This one‐step sonochemical strategy effectively addresses the long‐lasting limitations of traditional multistep synthesis, paving a fast and sustainable avenue to diversified metal/COF hybrids for heterogeneous catalysis and potentially other applications.
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Vapor‐Phase Synthesis of Electrocatalytic Covalent Organic Frameworks
Abstract The inability to process many covalent organic frameworks (COFs) as thin films plagues their widespread utilization. Herein, a vapor‐phase pathway for the bottom‐up synthesis of a class of porphyrin‐based COFs is presented. This approach allows integrating electrocatalysts made of metal‐ion‐containing COFs into the electrodes’ architectures in a single‐step synthesis and deposition. By precisely controlling the metal sites at the atomic level, remarkable electrocatalytic performance is achieved, resulting in unprecedentedly high mass activity values. How the choice of metal atoms, i.e., cobalt and copper, can determine the catalytic activities of POR‐COFs is demonstrated. The theoretical data proves that the Cu site is highly active for nitrate conversion to ammonia on the synthesized COFs.
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- PAR ID:
- 10483448
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 36
- Issue:
- 14
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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