Triarylboron‐Linked Conjugated Microporous Polymers: Sensing and Removal of Fluoride Ions

<jats:title>Abstract</jats:title><jats:p>A luminescent conjugated microporous polymer (BCMP‐3) has been synthesized in high yield by a carbon–carbon coupling reaction using triarylboron as a building unit. BCMP‐3 was fully characterized by using powder X‐ray diffraction analysis, Fourier transform infrared spectroscopy, <jats:sup>13</jats:sup>C solid‐state NMR spectroscopy, field emission scanning electron microscopy, thermogravimetric analysis, and nitrogen and carbon dioxide adsorption. The new three‐dimensional conjugated framework possess a high Brunauer–Emmett–Teller (BET) specific surface area up to 950 m<jats:sup>2</jats:sup> g<jats:sup>−1</jats:sup> with a pore volume of 0.768 cm<jats:sup>3</jats:sup> g<jats:sup>−1</jats:sup>, good stability, and abundant boron sites in the skeleton. Under excited‐light irradiation, BCMP‐3 exhibits strong fluorescent emission at 488 nm with a high absolute quantum yield of 18 % in the solid state. Polymer BCMP‐3 acts as a colorimetric and fluorescent chemosensor with high sensitivity and selectivity for F<jats:sup>−</jats:sup> over other common anions. In addition, the polymer also works as an adsorbent for F<jats:sup>−</jats:sup> removal and shows good adsorption capacities of up to 24 mg g<jats:sup>−1</jats:sup> at equilibrium F<jats:sup>−</jats:sup> concentrations of 16 mg L<jats:sup>−1</jats:sup> and a temperature of 298 K. The adsorption kinetics and isotherm were analyzed by fitting experimental data with pseudo‐second‐order kinetics and Langmuir equations. Furthermore, we highlight that BCMP‐3 is an adsorbent for fluoride removal that can be efficiently reused many times without loss of adsorption efficiency.</jats:p>