Two
novel lanthanide metal–organic frameworks (MOFs) with
the formulas [Tb(bidc)(Hbidc)(H2O)]
n
(JXUST-20) and {[Tb3(bidc)4(HCOO)(DMF)]·solvents}
n
(JXUST-21) were synthesized based on 2,1,3-benzothiadiazole-4,7-dicarboxylic
acid (H2BTDC) under solvothermal conditions. Interestingly,
benzimidazole-4,7-dicarboxylic acid (H2bidc) was formed
in situ using H2BTDC as the starting material. The self-assembly
process of the targeted MOFs with different topological structures
can be controlled by the solvents and concentration of the reactants.
Luminescence experiments show that JXUST-20 and JXUST-21 exhibit strong yellow-green emission. JXUST-20 and JXUST-21 can selectively sense benzaldehyde (BzH)
via a luminescence quenching effect with detection limits of 15.3
and 1.44 ppm, respectively. In order to expand the practical application
of MOF materials, mixed-matrix membranes (MMMs) have been constructed
by mixing targeted MOFs and poly(methyl methacrylate) in a N,N-dimethylformamide (DMF) solution, which
can also be used for BzH vapor sensing. Therefore, the first case
of MMMs derived from TbIII MOFs has been developed for
the reversible detection of BzH vapor, providing a simple and efficient
platform for the future detection of volatile organic compounds.