Electron field emission from magnetic nanomaterial encapsulated multi-walled carbon nanotubes

Applied Physics A (Impact Factor: 1.69). 01/2010; 98(1):195-202. DOI: 10.1007/s00339-009-5373-1

ABSTRACT The present work describes the field emission characteristics of nanoscale magnetic nanomaterial encapsulated multi-walled
carbon nanotubes (MWNTs) fabricated over flexible graphitized carbon cloth. Ni/MWNTs, NiFe/MWNTs and NiFeCo/MWNTs have been
synthesized by catalytic chemical vapor decomposition of methane over Mischmetal (Mm)-based AB3 (MmNi3, MmFe1.5Ni1.5 and MmFeCoNi) alloy hydride catalysts. Metal-encapsulated MWNTs exhibited superior field emission performance than pure MWNT-based
field emitters over the same substrate. The results indicate that a Ni-filled MWNT field emitter is a promising material for
practical field emission application with a lowest turn-on field of 0.6V/μm and a high emission current density of 0.3mA/cm2 at 0.9V/μm.

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