A highly sensitive and selective turn-off fluorescence sensor for Fe3+ detection based on a terbium metal-organic framework

摘要

A hydrothermal reaction of 1,3-di(3',5'-dicarboxylphenyl)benzene (H(4)ddb) with Tb3+ gave out a metal-organic framework material (Tb-MOF). Tb-MOF emitted green fluorescence, assigned to the characteristic transitions D-5(4) -> F-7(J) (J = 6-3) of Tb3+. Screening detected metal cations indicated that only Fe3+ can completely quench the fluorescence of Tb-MOF in the twenty optional ions. The sensitivity test of Tb-MOF showed a linear response of I-0/I = 55.2061. CFe3+ + 1.24077 in the CFe3+ range of 3.3 x 10(-4)-0.033 mmol L-1 with LOD being 0.936 mu M. Sixteen metal cations and four anions in the selectivity test did not influence the detection performances of TbMOF to Fe3+. The emission intensities of D-5(4) -> F-7(5) at 545 nm of Tb3+ can basically be recovered during a four-time quenching-recovery cycle in the durability test. Tb-MOF is a quantitative turn-off fluorescence sensor to Fe3+ detection with high sensitivity and selectivity, rapid response and a certain durability.