Summary: | 碩士 === 國立暨南國際大學 === 應用化學系 === 106 === A series of fluorescent metal-organic frameworks (MOFs) [Zn2(1,4-bdc)2(NI-mbpy-34)] (1, 1,4-H2bdc = benzene-1,4-dicarboxylic acid)、[Zn2(NH2-1,4-bdc)2(NI-mbpy-34)] (2, NH2-1,4-H2bdc = 2-aminobenzene-1,4-dicarboxylic acid)、[Zn(NO2-1,4-bdc)(NI-mbpy-34)] (3, NO2-1,4-H2bdc = 2-nitrobenzene-1,4-dicarboxylic acid) consisting of Zn(II), N-(pyridin-3-ylmethyl)-4-(pyridin-4-yl)-1,8-naphthalimide (NI-mbpy-34), and dicarboxylates were synthesized. Compound 1 is a 2D layer structure of trigonal prismatic cages with porosity of 24.8%. Compound 2 is a 3D primitive cubic type pillared-layer framework with porosity of 27.0%, which is 2-fold interpenetration. Compound 3 is a 3D nonporous primitive cubic type pillared-layer framework.
Compounds 1 and 2 have shown moderate CO2 adsorption abilities, with values of 69.5 cm3/g and 94.4 cm3/g, respectively, at 195 K and P/P0 = 1, but poor N2 uptakes, with values of 24.7 cm3/g and 9.5 cm3/g, respectively, at 77 K and P/P0 = 1. After adding nitro compounds to methanol suspensions of 1 and 3, their luminescence emissions would be efficiently quenched by a series of nitroaromatics, involving 2-nitrophenol (2-NP), 3-nitrophenol (3-NP), 4-nitrophenol (4-NP), 4-nitrotoluene (4-NT), 2,4-dinitrotoluene (2,4-DNT) and 1,4-dinitrobenzene (1,4-DNB), but not by nitrobenzene (NB) and aliphatic nitro compounds, such as nitromethane (NM) and 2,3-dimethyl-2,3-dinitrobutane (DMNB).
We have further studied on vapor-sensing of 1 and 3 toward volatile nitro and organic compounds. The results show that the emissions of zinc MOFs did not effectively affected by both series of analytes, leading to inefficient detection for volatile nitro and organic compounds.
Studies on adsorption of volatile iodine showed that 1 can adsorb iodine molecules, resulting in significant crystal color change from colorless to brown and more than 50% fluorescence quenching.
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