TY - JOUR
T1 - Soft X-ray spectroscopy studies of adsorption and reaction of CO in the presence of H2 over 6 nm MnO nanoparticles supported on mesoporous Co3O4
AU - Ralston, Walter T.
AU - Musselwhite, Nathan
AU - Kennedy, Griffin
AU - An, Kwangjin
AU - Horowitz, Yonatan
AU - Cordones, Amy A.
AU - Rude, Bruce
AU - Ahmed, Musahid
AU - Melaet, Gerome
AU - Alayoglu, Selim
N1 - Publisher Copyright:
© 2015 Elsevier B.V. All rights reserved.
PY - 2016/6
Y1 - 2016/6
N2 - MnO nanoparticles (6 nm) were supported on mesoporous spinel Co3O4 and studied using ambient pressure X-ray photoelectron spectroscopy (APXPS) and in situ X-ray absorption spectroscopy (XAS) during hydrogenation of CO. The nature and evolution of surface adsorbed species as well as the oxidation states of the metal oxide surfaces were evaluated under oxidizing, reducing, and H2 + CO (2:1) reaction atmospheres. From APXPS, MnO nanoparticle surfaces were found to be progressively reduced in H2 atmospheres with increasing temperature. Surface adsorbed CO was found to be formed at the expense of lattice O under H2 + CO reaction conditions. In situ XAS indicated that the dominant oxide species were Co(OH)2, Co (II) oxides, MnO, and Mn3O4 under reaction conditions. In situ XAS also indicated the formation of gas phase CO2, the disappearance of lattice O, and the further reduction of Mn3O4 to MnO upon prolonged reaction in H2 + CO. Mass spectroscopy measurements showed the formation of CO2 and hydrocarbons. The spent catalyst was investigated using scanning transmission X-ray microscopy and (scanning) transmission electron microscopy; the catalyst grains were found to be homogeneous.
AB - MnO nanoparticles (6 nm) were supported on mesoporous spinel Co3O4 and studied using ambient pressure X-ray photoelectron spectroscopy (APXPS) and in situ X-ray absorption spectroscopy (XAS) during hydrogenation of CO. The nature and evolution of surface adsorbed species as well as the oxidation states of the metal oxide surfaces were evaluated under oxidizing, reducing, and H2 + CO (2:1) reaction atmospheres. From APXPS, MnO nanoparticle surfaces were found to be progressively reduced in H2 atmospheres with increasing temperature. Surface adsorbed CO was found to be formed at the expense of lattice O under H2 + CO reaction conditions. In situ XAS indicated that the dominant oxide species were Co(OH)2, Co (II) oxides, MnO, and Mn3O4 under reaction conditions. In situ XAS also indicated the formation of gas phase CO2, the disappearance of lattice O, and the further reduction of Mn3O4 to MnO upon prolonged reaction in H2 + CO. Mass spectroscopy measurements showed the formation of CO2 and hydrocarbons. The spent catalyst was investigated using scanning transmission X-ray microscopy and (scanning) transmission electron microscopy; the catalyst grains were found to be homogeneous.
KW - Ambient pressure X-ray photoelectron spectroscopy
KW - CO hydrogenation
KW - In situ X-ray absorption spectroscopy
KW - Manganese oxide nanoparticles
KW - Mesoporous spinel cobalt oxide
UR - http://www.scopus.com/inward/record.url?scp=84958182888&partnerID=8YFLogxK
U2 - 10.1016/j.susc.2015.12.006
DO - 10.1016/j.susc.2015.12.006
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AN - SCOPUS:84958182888
SN - 0039-6028
VL - 648
SP - 14
EP - 22
JO - Surface Science
JF - Surface Science
ER -