Proton conduction and impedance sensing of a highly stable copper-organic framework from imidazole dicarboxylate

摘要

We have successfully synthesized a novel one-dimensional MOF, [Cu-4(HDMPhIDC)(4)(H2O)(4)](n) (1) by solvothermal method with the ligand 2-(3,4-dimethyl)phenyl-4,5-imidazole dicarboxylic acid (H3DMPhIDC). After analyzing its crystal structure, we have verified water stability, acid-base stability and adsorption properties of 1. We have measured the proton conductivity of 1 under water vapor and found the proton conductivity of 1 being 2.58 x 10(-5) S.cm(-1) at 98% relative humidity (RH) and 100 degrees C. Interestingly, MOF 1 shows good ammonia identification. The minimum ammonia sensing concentration is 10 ppm to be recognized by 1 at 25 degrees C. The lower the RH is, the more apparent the identification for ammonia is. When RH is 85% and the ammonia concentration in the system increases from 0 to 60 ppm, the impedance value of 1 is reduced from 4.29 x 10(8) to 1.07 x 10(6) Omega with high response of 39993%. (C) 2018 Elsevier Ltd. All rights reserved.