Full-Dimensional Control of Covalent Organic Frameworks Through Repulsion-Torsion Effect: Prominent 1D Above 2D and
Kaifu Yu1, Pan He1, Dong Zhang2
1College of Chemistry, Sichuan University, Chengdu, 610064, P.R. China.
Angewandte Chemie (International Ed. in English)
|July 25, 2025
Summary
This study synthesized novel one-, two-, and three-dimensional covalent organic frameworks (COFs) by controlling molecular building block conformations. The 1D COF exhibited superior charge transfer and photocatalytic performance due to unique rotational restrictions.
Area of Science:
- Materials Science
- Chemistry
- Nanotechnology
Background:
- Designing advanced covalent organic frameworks (COFs) requires understanding how dimensionality impacts their properties.
- Simultaneous synthesis and study of 1D, 2D, and 3D COFs have been challenging due to difficulties in dimensional control.
Purpose of the Study:
- To synthesize novel 1D, 2D, and 3D COFs from similar compositions.
- To investigate the influence of molecular building block conformation on COF dimensionality.
- To explore the relationship between COF dimension and properties like charge transfer and photocatalysis.
Main Methods:
- Manipulation of molecular building block conformation via the repulsion-torsion effect to control dimensionality.
- Synthesis of three novel COFs with distinct dimensions (1D, 2D, 3D).
- Evaluation of charge transfer efficiency and photocatalytic performance across the synthesized COFs.
Main Results:
- Successfully synthesized 1D, 2D, and 3D COFs by tuning the repulsion-torsion effect.
- A strong repulsion-torsion effect led to non-planar building blocks and 2D/3D COF formation.
- Reduced repulsion-torsion effect resulted in a rare 1D COF structure.
- Observed a performance order of 1D > 3D > 2D for charge transfer efficiency and photocatalysis.
Conclusions:
- The repulsion-torsion effect is a viable strategy for controlling COF dimensionality.
- The 1D COF's superior performance is attributed to the in-plane and out-of-plane double rotational restriction (IODRR) effect.
- IODRR stabilizes the aromatic framework, reducing carrier recombination and energy loss, enhancing photocatalytic activity.
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