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Abstract Covalent organic frameworks (COFs) are promising for catalysis, sensing, gas storage, adsorption, optoelectricity, etc. owning to the unprecedented combination of large surface area, high crystallinity, tunable pore size, and unique molecular architecture. Although COFs are in their initial research stage, progress has been made in the design and synthesis of COF‐based electrocatalysis for the oxygen reduction reaction, oxygen evolution reaction, hydrogen evolution reaction, and CO2reduction in energy conversion and fuel generation. Design principles are also established for some of the COF materials toward rational design and rapid screening of the best electrocatalysts for a specific application. Herein, the recent advances in the design and synthesis of COF‐based catalysts for clean energy conversion and storage are presented. Future research directions and perspectives are also being discussed for the development of efficient COF‐based electrocatalysts.
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Enhanced Crystallinity of Covalent Organic Frameworks Formed Under Physical Confinement by Exfoliated Graphene
Abstract The polymerization of 1,4‐benzenediboronic acid (BDBA) on mica to form a covalent organic framework (COF‐1) reveals a dramatic increase in crystallinity when physically confined by exfoliated graphene. COF‐1 domains formed under graphene confinement are highly geometric in shape and on the order of square micrometers in size, while outside of the exfoliated flakes, the COF‐1 does not exhibit long‐range mesoscale structural order, according to atomic force microscopy imaging. Micro‐Fourier transform infrared spectroscopy confirms the presence of COF‐1 both outside and underneath the exfoliated graphene flakes, and density functional theory calculations predict that higher mobility and self‐assembly are not causes of this higher degree of crystallinity for the confined COF‐1 domains. The most likely origin of the confined COF‐1's substantial increase in crystallinity is from enhanced dynamic covalent crystallization due to the water confined beneath the graphene flake.
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- PAR ID:
- 10373564
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 18
- Issue:
- 46
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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