Indexed by:
Journal Papers
First Author:
Dong, Cui
Correspondence Author:
Qu, ZP (reprint author), Dalian Univ Technol, Sch Environm Sci & Technol, Key Lab Ind Ecol & Environm Engn MOE, Linggong Rd 2, Dalian 116024, Peoples R China.
Co-author:
Qu, Zhenping,Jiang, Xiao,Ren, Yewei
Date of Publication:
2020-06-05
Journal:
JOURNAL OF HAZARDOUS MATERIALS
Included Journals:
PubMed、EI、SCIE
Document Type:
J
Volume:
391
Page Number:
122181
ISSN No.:
0304-3894
Key Words:
Oxygen vacancy; Toluene oxidation; Two-dimensional MnO2; Cu doping; In
situ DRIFTS
Abstract:
Oxygen vacancy acts an important role in adjusting the chemical properties of MnO2. In this paper, two-dimensional MnO2 catalysts with different oxygen vacancy concentration are obtained by doping Cu2+. It is researched that the K+ species in the interlayer of birnessite-type MnO2 can be substituted during the Cu2+ doping process. Meanwhile, this process will generate the oxygen vacancy. Interestingly, the formation of an appropriate numbers of oxygen vacancy in MnO2 distinctly enhances the low-temperature reducibility and oxygen species activity, which improves the catalytic activity for the toluene oxidation (T-100 = 220 degrees C, E-a= 43.6 kJ/ mol). However, an excessive concentration of oxygen vacancy in MnO2 sample performs against the activity improvement for toluene oxidation. In situ DRIFTS are applied to elucidate the main intermediates and conversion pathway on MnO2-OV3 with moderate concentration of oxygen vacancy. The results demonstrate that the adsorbed toluene can interact with oxygen species of catalyst to form physisorbed benzaldehyde, aldehydic adsorbate and benzoate species. In addition, it is found that the oxygen vacancy concentration plays an important effect on the oxidation of benzoate species owing to the acceleration effect of oxygen vacancy in the activation of gaseous oxygen.
Translation or Not:
no
