A novel hybrid Bi2MoO6-MnO2 catalysts with the superior plasma induced pseudo photocatalytic-catalytic performance for ethyl acetate degradation

摘要

A hybrid catalyst system of Bi2MoO6-MnO2 was designed and applied in a plasma system for the degradation of ethyl acetate (EA). This hybrid catalyst greatly improved the utilization of plasma-generated species like high-energy electrons, O and O-3. In addition, an excellent removal efficiency of EA (100%), selectivity of CO2 (70%) and selectivity of COx (99%) at a specific input energy of 392 J/L were achieved compared to the pure catalyst materials or plasma alone. The enhanced discharge intensity of the plasma, adsorption capability for EA, and oxidation capability of the hybrid catalyst in plasma made simultaneous contributions to this improved performance. A synergetic effect between Bi2MoO6 and MnO2 evidently occurred, showing that h(+) generated from Bi2MoO6 by "pseudo photocatalysis" can induce the transformation of Mn3+ to Mn4+ of MnO2 in plasma. Further, Fourier transform infrared (FT-IR) spectra and gas chromatography mass spectrometry (GC-MS) results indicated that the degradation of EA firstly took place on the surface of the hybrid Bi2MoO6-MnO2 catalyst in the plasma environment, along with the formation of by-products like acetic acid, acetone and CH4. Then, the by-products were converted to COx by the oxidation of O-3. This novel strategy of integrating the contributions of photocatalyst and thermocatalyst in a plasma environment described in this work should inspire the rational design of more catalysts for plasma-catalyst systems for the purification of environmental pollutants.