A new bimetallic lanthanide metal-organic framework as a self-calibrating sensor for formaldehyde

We have designed and synthesized a new material of bimetallic lanthanide metal-organic framework [Eu3.2Gd0.8(NDC)(6)(H2O)(5)]center dot 3H(2)O(Eu8Gd2-NDC NDC = Naphthalene-2,6-dicarboxylic acid) with dual emission. The structure, composition and morphology of the Eu8Gd2-NDC were characterized by XRD, SEM and FT-IR respectively. The Eu8Gd2-NDC exhibits a highly detectable luminescence in response to formaldehyde (HCHO). The luminescence intensity (I-453/I-616) increases linearly with increasing HCHO content in the range from 0.05 to 2.5%. The sensing mechanism was also discussed. A paper strip coated with Eu8Gd2-NDC material was also shown to be highly selective for formaldehyde. This is the first demonstrated self-calibrating luminescent sensor for small molecules based on the bimetallic lanthanide metal-organic framework. (C) 2018 Elsevier B.V. All rights reserved.