Covalent organic frameworks (COFs) represent an emerging class of two- or three-dimensional crystalline porous materials with delicate control over topology, composition, and porosity. Here, we develop a new COF made up of 1,3,6,8-tetrakis­(p-formylphenyl)­pyrene (TFPPy) and 4,4′-diaminobenzophenone (DABP) that exhibits a rare one-dimensional (1D) structure. The resulting frameworks possess good crystallinity, comparatively high Brunauer–Emmett–Teller (BET) surface area (426 m2/g), and good thermal stability (360 °C). Impressively, this 1D COF shows strong fluorescence and can be used as an excellent H+ sensor in an acidic aqueous solution.

Covalent organic frameworks (COFs) have been extensively investigated due to their unique structure, porosity, and functionality. However, at the topological level, COFs remain as two‐dimensional (2D) or three‐dimensional (3D) structures, while COFs with one‐dimensional (1D) topology have not been systematically explored. In this work, we proposed a synthetic strategy for the construction of 1D‐COFs based on non‐linear edges and suitable high‐symmetry vertices. Compared with their 2D‐COFs counterparts, the 1D‐COFs with AIEgens located at the vertex of the frame exhibited enhanced fluorescence. The density functional theory (DFT) calculations revealed that the dimensional‐induced rotation restriction (DIRR) effect could spontaneously introduce additional non‐covalent interactions between the strip frames, which could substantially diminish non‐radiative transitions. This work also provides protocols for the design of 1D‐COFs and a guidance scheme for the synthesis of emitting COFs.

The strategic implementation of using a core-substituted naphthalene diimide derivative to electropolymerize an ionized polymer for a better electrochromic performance is proposed.

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