Synthesis of Cu-doped MOF-235 for the Degradation of Methylene Blue under Visible Light Irradiation

Cu-doped MOF-235 particles with various Cu concentrations were successfully prepared using the solvothermal method and investigated for the degradation of methylene blue (MB) under visible light irradiation. The structural properties of the MOF-235 samples were affected by the Cu concentrations. The particle size, surface area, and pore volume of the sample were decreased gradually with increasing of Cu amount. The photocatalytic degradation of MB indicated that Cu-doped MOF-235 outperformed pure MOF-235 and commercial TiO ₂ due to presence of Cu ⁺ and Cu ²⁺ species suppress the electron–hole recombination. After 8 h of photocatalytic degradation of MB, 40% of the Cu-doped MOF-235 sample exhibited the highest degradation efficiency of 90%, while pure MOF-235 and commercial TiO ₂ showed the degradation efficiencies of 10 and 5%, respectively.