Crystallography and elasticity of individual GaN nanotubes.
High-purity, crystalline [001]-oriented GaN nanotubes with outer diameters of 200 nm or more, rough surfaces and irregular internal channels were synthesized under epitaxial growth on [001]-oriented sapphire substrates. Elastic property measurements on free-standing individual GaN nanotubes, using the in situ transmission electron microscopy (TEM) electromechanical resonance technique, pointed at an average Young's modulus E of 37 GPa and minimum quality factor of 320. These numbers are notably lower than those for previously reported GaN nanowires. The crystallography and chemistry of the GaN nanotubes were analyzed using TEM and energy dispersion x-ray spectroscopy (EDS). It is suggested that the lowered Young's modulus and quality factor of the nanotubes are mainly due to the surface roughness and defectiveness.
WPI Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), Namiki 1-1, Tsukuba, Ibaraki 305-0044, Japan. baodanliu@gmail.com
Baodan
B
Liu
Yoshio
Y
Bando
Mingsheng
M
Wang
Chengchun
C
Tang
Masanori
M
Mitome
Dmitri
D
Golberg
D003460:Crystallization / Q000379:methods*; D055119:Elastic Modulus; D005708:Gallium / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D013314:Stress, Mechanical; D013499:Surface Properties
D046911:Macromolecular Substances; C473348:gallium nitride; D005708:Gallium