A hybrid catalyst for decontamination of organic pollutants based on a bifunctional dicopper(II) complex anchored over niobium oxyhydroxide

Abstract

This article describes the preparation and characterization of a hybrid oxidation catalyst for decontamination of organic pollutants which involves a bifunctional dicopper(II) complex and the niobium(V) oxyhydroxide as the active species, the later one being also a solid support. The pH range for the existence of the active species was determined by potentiometric and UV–vis spectroscopy at 25°C and 0.15M NaCl in a H2O/EtOH (70:30 v/v) solvent mixture containing copper(II) and the ligand N,Ń-2,2′-ethylenediphenylenebis(oxamic acid) (H4L). As far as the hybrid material is concerned, FTIR, FT-Raman, TEM and SEM images, surface area and TG/DTA analyses showed the occurrence of a chemical interaction between the dicopper(II) complex and the surface hydroxo groups of the niobium oxyhydroxide whereas ESI–MS and UV–vis spectroscopy evidence a total disappearance of the signals due to the organic dye which is used as model molecule. This hybrid material seems to combine the different properties of the components increasing its catalytic activity for oxidizing organic pollutants at different pH values.