Ni–Mo and Co–Mo alloy nanoparticles for catalytic chemical vapor deposition synthesis of carbon nanotubes

• Published in: Journal of alloys and compounds Vol. 621; pp. 351 - 356
• Main Authors: Lobiak, E.V., Shlyakhova, E.V., Bulusheva, L.G., Plyusnin, P.E., Shubin, Yu.V., Okotrub, A.V.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05-02-2015
• Subjects: Carbon nanotubes; Catalysis; Catalysts; CCVD synthesis; Chemical vapor deposition; Clusters; Co–Mo alloy; Nanoparticles; Nickel base alloys; Ni–Mo alloy; Polyoxomolybdates; Synthesis; Thermal analysis; X-rays; Ni–Mo alloy; Polyoxomolybdates; Carbon nanotubes; Thermal analysis; CCVD synthesis; Co–Mo alloy
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2014.09.220

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•Thermal decomposition of the ε-Keggin-type polyoxomolybdate clusters Mo12O28(μ2-OH)12{Ni(H2O)3}4 and Mo12O28(μ2-OH)12{Co(H2O)3}4 produces NiMoO4 and CoMoO4 phases.•The NiMoO4 and CoMoO4 phases are converted in alloys with a metal ratio of 1:1.•The Ni–Mo and Co–Mo alloy nanoparticles catalyze a CCVD growth of carbon nanotubes.
Here, we show for the first time a catalytic chemical vapor deposition (CCVD) synthesis of carbon nanotubes (CNTs) using polyoxomolybdate clusters Mo12O28(μ2-OH)12{Ni(H2O)3}4 and Mo12O28(μ2-OH)12{Co(H2O)3}4 as a source of catalyst nanoparticles. X-ray diffraction analyses indicated that the products of thermal decomposition of the clusters contain NiMoO4 and CoMoO4 phases, which are converted into Ni–Mo and Co–Mo alloys at 900°C in hydrogen environment. High-resolution transmission electron microscopy in combination with energy-dispersive X-ray spectroscopy confirmed the CNT growth from bimetallic nanoparticles. Synergism between two metals in an alloy resulted in large-scale production of non-bundled few-walled CNTs with narrow diameter distribution and high quality.