An indole-derived porous organic polymer for the efficient visual colorimetric capture of iodine in aqueous media via the synergistic effects of cation-π and electrostatic forces.

We have successfully synthesized a novel type of recyclable indole-based porous polymer, which possesses highly effective capture behavior for iodine in aqueous solution via the synergistic effects of cation-π and electrostatic forces. More interestingly, the absorption performance can be efficiently detected via a visual colorimetric assay using a smartphone.