Highly dispersed Mn2O3-Co3O4 nanostructures on carbon matrix as heterogeneous Fenton-like catalyst

This work reports the synthesis of various carbon (Vulcan XC-72 R) supported metal oxide nanostructures, such as Mn2O3, Co3O4 and Mn2O3-Co3O4 as heterogeneous Fenton-like catalysts for the degradation of organic dye pollutants, namely Rhodamine B (RB) and Congo Red (CR) in wastewater. The activity results showed that the bimetallic Mn2O3-Co3O4/C catalyst exhibits much higher activity than the monometallic Mn2O3/C and Co3O4/C catalysts for the degradation of both RB and CR pollutants, due to the synergistic properties induced by the Mn-Co and/or Mn (Co)-support interactions. The degradation efficiency of RB and CR was considerably increased with an increase of reaction temperature from 25 to 45 degrees C. Importantly, the bimetallic Mn2O3-Co3O4/C catalyst could maintain its catalytic activity up to five successive cycles, revealing its catalytic durability for wastewater purification. The structure-activity correlations demonstrated a probable mechanism for the degradation of organic dye pollutants in wastewater, involving center dot OH radical as well as Mn2+/Mn3+ or Co2+/Co3+ redox couple of the Mn2O3-Co3O4/C catalyst.