AIE-ligand-based luminescent Cd(ii)-organic framework as the first "turn-on" Fe3+ sensor in aqueous medium

Excess iron ions are harmful to human health; therefore, it is essential to develop efficient methods to detect Fe3+. Herein, a new aggregation-induced emission (AIE) ligand (L), 4,4 '-((9H-fluoren-9-ylidene)-methylene)dipyridine, was successfully synthesized and applied to construct a luminescent Cd(ii)-organic framework [Cd(NDA)(L)(H2O)(2)](n) (1) with a two-dimensional architecture (H(2)NDA = 1,4-naphthalenedicarboxylic acid). Specially, 1 possesses good water stability and exhibits superior luminescence enhancement ("turn-on") sensing of Fe3+ with high sensitivity and selectivity in a water suspension. This represents the first example of a LMOF-based "turn-on" Fe3+ sensor in aqueous medium.