Synthesis of Cu/C composite materials by anaerobic pyrolysis of Cu-MOF and application as catalyst for the 4-nitrophenol decomposition reaction

Abstract

A copper-based metal-organic framework (Cu-MOF) was successfully synthesised via a solvothermal method by reacting CuCl₂·2H₂O and 1,4-benzenedicarboxylic acid (H₂BDC) in a water/DMF (1:1, v/v) solvent mixture at 100°C for 24 hours. The Cu-MOF precursor underwent carbonisation at 600°C for 1 hour under an argon atmosphere and successfully obtained C@Cu-MOF. Powder X-ray diffraction (PXRD) analysis confirmed the complete transformation of diffraction peaks corresponding to the crystalline phase of Cu-MOF to diffraction peaks of metallic copper with C@Cu-MOF material. Scanning electron microscope (SEM) images of C@Cu-MOF illustrate microsized needle-like crystals. After carbonisation, SEM images of C@Cu-MOF show the formation of metallic copper nanoparticles distributed on the material’s framework. The catalytic performance of C@Cu-MOF was tested in the reduction of the  environmental pollutant 4-nitrophenol using NaBH4 as a reducing agent. The results were compared with previous studies based on noble metal and transition metal nanocatalysts, demonstrating that C@Cu-MOF exhibits high catalytic activity. After being reused in three consecutive reactions, the catalytic activity decreased insignificantly (<3%), demonstrating the high durability of the catalyst.