Mo and MoO3 powders: Structure and resistance to CO

• Published in: Journal of alloys and compounds Vol. 615; pp. 784 - 791
• Main Author: Novoselova, L.Yu
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.12.2014
• Subjects: Metals; MoO3/Mo2C/Mo/Mo4O11; Nanostructures; Optical spectroscopy; X-ray diffraction; X-ray diffraction; Mo; Optical spectroscopy; Nanostructures; Metals; MoO3/Mo2C/Mo/Mo4O11
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2014.07.006

•Mo NP contained 88.2% molybdenum and 11.5% oxygen and showed resistance to CO at 200°C.•MoO3 MP was obtained via the thermal treatment of the Mo NP.•MoO3 MP contained 67.5% molybdenum and 32.3% oxygen.•Mo2C and Mo crystallites were identified in MoO3 MP sample treated with CO at 200°C. A molybdenum trioxide micropowder (МоО3 MP) with an average crystallite size of 821nm was obtained by the thermal treatment of an initial molybdenum nanopowder (Mo NP) with an average crystallite size of 150nm. The structure of these powders and their resistance to carbon monoxide action at an increased temperature were studied by X-ray diffraction, X-ray fluorescence, and IR spectroscopy. The Mo NP sample contained 88.25% molybdenum and 11.51% oxygen and, as a whole, showed resistance to CO action at 200°C. However, its crystallites were observed to grow under the specified conditions, and their final average size exceeded 1000nm. The obtained MoO3 MP sample contained 67.50% molybdenum and 32.34% oxygen. Мо2С, Мо and Мо4О11 were identified in addition to МоО3 after a treatment with CO at 200°C. It is concluded that the МоО3 MP is unstable under the action of carbon monoxide at the indicated temperature. It is suggested that a dissociative sorption of CO involving МоО3 occurs.