Porous organic polymer nanotubes as luminescent probe for highly selective and sensitive detection of Fe^(3+)

Two porous organic polymer nanotubes(PNT-2 and PNT-3) were synthesized via Ni-catalyzed Yamamoto reaction, using2,4,6-tris-(4-bromo-phenyl)-[1,3,5]-triazine(TBT) as one monomer, and 2,7-dibromopyrene(DBP) or 1,3,6,8-tetrabromopyrene(TBP) as another monomer. The scanning electron microscope(SEM) images show that both PNT-2 and PNT-3 possess clear hollow tube structures. Luminescent measurements indicate that both PNT-2 and PNT-3 can serve as luminescent probe for highly selective and sensitive detection of Fe^(3+) by luminescent quenching effect. Absorption competition quenching(ACQ) mechanism is also proposed to explain luminescent quenching behavior, i.e., the overlap of the UV-spectra between Fe^(3+) and PNTs causes the energy competition, and therefore leads to luminescent quenching. Moreover, both PNT-2 and PNT-3 still show high selectivity and sensitivity for sensing Fe^(3+) in 10% ethanol aqueous solution, which means that the two porous PNTs are promising candidates as luminescent probes for detecting Fe^(3+) in practical applications.