화학공학소재연구정보센터
Applied Catalysis B: Environmental, Vol.224, 634-647, 2018
Insight into pathways of methylene blue degradation with H2O2 over mono and bimetallic Nb, Zn oxides
The aim of this work was to investigate the influence of surface properties of metal oxides (Nb2O5, ZnO and ZnNb2O6) on the type of reactive oxygen species (ROS) formed in contact with hydrogen peroxide, and to determine the effect of zinc addition to niobium pentoxide on the type of ROS formed and its activity in methylene blue degradation. The structure and surface properties of materials synthesized were characterized by nitrogen adsorption, XRD, XPS, SEM, SEM-EDX, DR UV-vis and FTIR techniques. The ability of metal oxides to generate superoxo and peroxo species upon treatment with H2O2 was documented and discussed in respect to the type of metal oxide used. It was found that the distortion of NbO6 species in bimetallic oxide influenced the interaction of this mixed oxide with hydrogen peroxide. The oxidative properties of reactive oxygen species formed on the surface of metal oxides were tested in degradation of methylene blue. The activity of niobium(V) oxide in this process was much higher than that of mixed oxide and ZnO. In order to identify the reaction pathways on the basis of determination of the reaction intermediates, the reaction mixtures were analyzed by ESI-MS. On the basis of the results obtained the mechanism of the dye degradation was discussed.