Facile preparation of hypercrosslinked carbazole-based porous organic polymers via FeCl ₃ -promoted one-step oxidative coupling reaction and Friedel–Crafts alkylation from the vinyl or hydroxymethyl functionalized carbazole is reported.

Based on two new triscyclometallated iridium complexes containing carbazolyl groups, conjugated microporous polymers (CPOP-20 and CPOP-21) were obtained through a FeCl₃-promoted oxidative coupling reaction. Both of these complex monomers and their related polymers exhibit intense phosphorescence, which indicates that they are potential solid phosphorescent materials. The polymers are chemically and thermally stable, and show moderate Brunauer–Emmett–Teller specific surface area up to 480 m² g⁻¹. Furthermore, they are highly active in the heterogeneous photocatalytic aza-Henry reaction at room temperature for various substrates and show outstanding recycling performance with good retention of photoactivity over three cycles without a significant loss of conversion.

A convenient and rapid method that combines a fluorescent nanoprobe based on C-g-C ₃ N ₄ -Eu ³⁺ with a smartphone and test paper has been developed for the in situ detection of tetracyclines.