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Updated: Jan 8, 2026

Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

Published on: July 10, 2017

Ingeniería de la Anisotropía Intracapa en Redes Orgánicas Covalentes

Yao Chai¹, Yanmei Chen², Shu-He Han¹

¹Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, 999077, China.

Angewandte Chemie (International ed. in English)

|December 20, 2025

Abstract:

Precise control of intralayer anisotropy in two-dimensional covalent organic frameworks (COFs) remains a significant challenge in materials design. We address this through a mixed-linker strategy using 8-connected pyrene and triphenylamine monomers with 4-connected ETTA to form 1D nanoribbons. These ribbons are longitudinally stitched by diamines of programmable lengths, enabling precise in-plane anisotropy tuning. Shortening the linkers from biphenyl to phenyl (T-COF-2 → T-COF-1) induces compressive strain within the π-conjugated backbone, enhancing π-electron delocalization and boosting photogenerated charge carrier mobility by over fourfold. Consequently, T-COF-1 achieves a 93.81% conversion efficiency in visible-light-driven NADH (nicotinamide adenine dinucleotide) oxidation-a 4.26-fold enhancement over T-COF-2-along with a 1.41% apparent quantum yield at 420 nm. Remarkably, T-COF-1 retains substantial activity under 650 nm near-infrared light (14.67% conversion, 0.11% quantum yield), highlighting its potential for photodynamic therapy. This work establishes interchain covalent proximity as a design principle for rationally engineering high-performance COF photocatalysts, with broad implications for solar energy conversion and biomedical applications.

Palabras clave:

Transporte de carga Redes orgánicas covalentes Anisotropía intracapa Oxidación de NAD+Fotocatálisis

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