Construction of Donor–Acceptor-Type\nConjugated\nMicroporous Polymers by Oxidative Coupling of Boranil-Carbazole Mixed\nMonomers for Enhanced Photocatalytic Oxidation

Conjugated microporous polymers (CMPs), featuring photoactive\nstructures,\na high surface area, robust thermal stability, and facile modulation,\nprovide a versatile platform for fabricating diverse heterogeneous\nphotocatalysts. The incorporation of donor–acceptor (D–A)\nstructures into CMPs to increase their charge separation potential\nand enhance the photocatalytic efficacy is a viable strategy. In this\nwork, we designed and synthesized a unique set of D–A monomers,\nincorporating boranil dyes as electron-deficient moieties and carbazoles\nas electron-rich subunits. Subsequently, D–A CMPs were prepared\nvia an economical and environmentally friendly oxidation coupling\nreaction, and their potential in photocatalytic oxidation reactions\nwas investigated. Modulation of the polymer’s photoelectronic\nproperties and photocatalytic performance can be achieved by adjusting\nthe boranil content in the monomer. The polymer pCZFB-3, with the\nhighest content of boranil units, exhibited an optimal photocatalytic\nactivity. This finding confirms that strengthening the D–A\neffect can significantly enhance a catalyst’s photoelectronic\nproperties and catalytic efficacy. This study presents insights into\ndesigning innovative heterogeneous photocatalysts based on boron-containing\ndyes.