TY - JOUR
T1 - Nanotube growth during annealing of mechanically milled Boron
AU - Fitz Gerald, J. D.
AU - Chen, Y.
AU - Conway, M. J.
PY - 2003/1
Y1 - 2003/1
N2 - Boron powder, finely ground in a tungsten carbide ball mill in an ammonia atmosphere, has been annealed at 1200°C in flowing nitrogen to produce small quantities of cylindrical BN nanotubes, both as isolated individuals and grouped into ropes. Thick-walled conical BN tubes are abundant in specimens annealed for longer times, and their growth was catalysed once WC debris was converted into W metal particles. Some catalytic effect of small W nanoparticles could be necessary for nanotube formation, though no tip particles have been imaged here. Given the low temperature of mechanical milling and annealing. BN growth must involve surface diffusion and solid-state reconfiguration. It could be possible to engineer desirable physical and chemical properties by exploiting the variation in cylindrical versus conical BN structures as a function of annealing time.
AB - Boron powder, finely ground in a tungsten carbide ball mill in an ammonia atmosphere, has been annealed at 1200°C in flowing nitrogen to produce small quantities of cylindrical BN nanotubes, both as isolated individuals and grouped into ropes. Thick-walled conical BN tubes are abundant in specimens annealed for longer times, and their growth was catalysed once WC debris was converted into W metal particles. Some catalytic effect of small W nanoparticles could be necessary for nanotube formation, though no tip particles have been imaged here. Given the low temperature of mechanical milling and annealing. BN growth must involve surface diffusion and solid-state reconfiguration. It could be possible to engineer desirable physical and chemical properties by exploiting the variation in cylindrical versus conical BN structures as a function of annealing time.
UR - http://www.scopus.com/inward/record.url?scp=0037224998&partnerID=8YFLogxK
U2 - 10.1007/s00339-002-1441-5
DO - 10.1007/s00339-002-1441-5
M3 - Article
SN - 0947-8396
VL - 76
SP - 107
EP - 110
JO - Applied Physics A: Materials Science and Processing
JF - Applied Physics A: Materials Science and Processing
IS - 1
ER -