Fluorescence porous organic polymers synthesized via transition metal-free thiol‑yne click chemistry for fluorescence sensing bismuth triiodide

Bismuth tri-iodide (BiI 3 ) is commonly determined by spectrophotometric method and atomic absorption spectrometry (AAS) methods, which requires adding the appropriate color developer or re-extraction, and the operation is cumbersome. Herein, we developed the method of detecting BiI 3 with fluorescence spectroscopy for the first time. In this contribution, two novel thiol-linked POPs have been successfully synthesized by thioalk-ynes click polymerization. The chemical structures of the as-prepared thiol-linked POPs were characterized by FT-IR, ss 13 C NMR, UV–vis absorption spectra, and elemental analysis. The as-prepared thiol-linked POPs emit strong fluorescence in 1,4-dioxane (DOX) and could be used for selectively detection of BiI 3 with the high quenching constants of 4.04 × 10 4 and 4.35 × 10 4 L mol −1 , and with the low limits of detection (LODs) of 7.43 × 10 −10 and 6.90 × 10 −10 mol L −1 , respectively. The study of UV–vis absorption spectroscopy has proved that the specific fluorescence quenching process of the thiol-linked POPs to BiI 3 is an absorption competition quenching mechanism.