The synthesis of 1,6-disubstituted pyrene-based conjugated microporous polymers for reversible adsorbing and fluorescent sensing to iodine
Here we present detailed evidence of highly efficient iodine capture and sensing in 1,6-disubstituted pyrene-based fluorescent conjugated microporous polymers, which were synthesized by a Sonogashira–Hagihara polycondensation reaction (TDP), trimerization reaction of bi-cycano compound (CPP) catalyzed using trifluoromethanesulfonic acid (PCPP), and Friedel-Crafts reaction catalyzed with CH3SO3H (TTPDP and TDTPAP), respectively. TDP, PCCP, TTPDP, and TDTPAP have specific surface areas of 261.9, 43.0, 187.5, and 695.2 m2 g-1, and display reversible guest uptake of 0.61, 3.07, 3.49, 4.19 g g-1 in iodine vapor. The four CMPs exhibit high sensitivity and selectivity to iodine via fluorescence quenching. Furthermore, PCPP exhibited extremely high detection sensitivity to I2 with Ksv of 1.40×105 L mol-1 and detection limit of 3.14×10-13 mol L-1. To the best of our knowledge, it displays the highest reported Ksv value and the lowest detection limit value to iodine to date.