Synthesis,Characterization And Properties Of Trimesic Acid-based MOF-derived Magnetic Porous Carbon Materials

Metal Organic Frameworks?MOFs?are crystal materials that self-assemble from metal ions and organic ligands through coordination bonds.In recent years,the synthesis of magnetic porous carbon composites derived from MOFs precursors through a facile carbonization process has attracted much attention.Trimellitic acid is cheap and readily available.In this paper,we have prepared a series of trimesic acid-based MOFs by direct precipitation method.Magnetic porous carbon composites were prepared via the direct pyrolysis of MOF precursors,and then study their properties on dye adsorption and catalytic 4-NP reduction.1.A faciledirectprecipitationmethodwasusedtopreparethe[Ni₃?BTC?₂·12H₂O]at room temperature,and the magnetic Ni-carbon submicrorods were synthesized by direct pyrolysis of[Ni₃?BTC?₂·12H₂O]precursors at different temperatures.The resulting porous Ni/C submicrorods exhibited excellent catalytic activity for the reduction of 4-nitrophenol to 4-aminophenol,especially the sample synthesized at 800°C.The activity factor?(?=k/m,s^-11 g^-1)was found to be 17.41 s^-1g^-1,which is higher than most of reported Ni-based and noble metal-based catalysts.In addition,Ni/C-800 has excellent separation performance and reusability.After five cycles,there was no significant decrease in the catalytic activity of the catalyst.2.Ni/Zn-MOF precursors were rapidly synthesized by direct precipitation method under mild conditions,and the nickel/nanoporous carbon?Ni/NPC?composites were prepared by high-temperature calcination.The as-obtained Ni/NPC composites were characterized and used to remove malachite green?MG?,Congo red?CR?,Rhodamine B?RB?,methylene blue?MB?and methyl orange?MO?from aqueous solution.The results showed that the Ni/NPC composites have excellent adsorption properties for the five dyes,and the maximum adsorption capacities are about 898,818,395,312 and 271 mg/g,respectively,which is much higher than most of the previously reported adsorbents.3.The Co/C composites were prepared by calcining[Co₃?BTC?₂?H₂O?₁₂]precursors in N₂ atmosphere.The Co/C composites were used to remove MG from aqueous solution.The results showed that the maximum adsorption capacity was approximately4893mg/g,andtheadsorptionprocessfollowedthe pseudo-second-order kinetic model and Langmuir isotherm.