10.3929/ETHZ-B-000424499
Kurlov, Alexey
Huang, Xing
Deeva, Evgeniya B.
Abdala, Paula M.
Fedorov, Alexey
Müller, Christoph R.
Molybdenum carbide and oxycarbide from carbon-supported MoO3 nanosheets: phase evolution and DRM catalytic activity assessed by TEM and in situ XANES/XRD methods
ETH Zurich
2020
Journal Article
2020-06-28
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Molybdenum carbide (β-Mo2C) supported on carbon spheres was prepared via a carbothermal hydrogen reduction (CHR) method from delaminated nanosheets of molybdenum(vi) oxide (d-MoO3/C). The carburization process was followed by combined in situ XANES/XRD analysis revealing the formation of molybdenum oxycarbide Mo2CxOy as an intermediate phase during the transformation of d-MoO3/C to β-Mo2C/C. It was found that Mo2CxOy could not be completely carburized to β-Mo2C under a He atmosphere at 750 °C, instead a reduction in H2 is required. The β-Mo2C/C obtained showed activity and stability for the dry reforming of methane at 800 °C and 8 bar. In situ XANES/XRD evaluation of the catalyst under DRM reaction conditions combined with high resolution TEM analysis revealed the evolution of β-Mo2C/C to Mo2CxOy/C. Notably, the gradual oxidation of β-Mo2C/C to Mo2CxOy/C correlates directly with the increased activity of the competing reverse water gas shift reaction.
Nanoscale, 12 (24)
ISSN:2040-3364
ISSN:2040-3372