Zeng HB, Zhi CY, Zhang ZH, Wei XL, Wang XB, Guo WL, Bando Y, Golberg D
. "White Graphenes": Boron Nitride Nanoribbons via Boron Nitride Nanotube Unwrapping
. Nano Letters [Internet]. 2010;10:5049-5055. 访问链接Abstract
Inspired by rich physics and functionalities of graphenes, scientists have taken an intensive interest in two-dimensional (2D) crystals of h-BN (analogue of graphite, so-called "white" graphite). Recent calculations have predicted the exciting potentials of BN nanoribbons in spintronics due to tunable magnetic and electrical properties; however no experimental evidence has been provided since fabrication of such ribbons remains a challenge. Here, we show that few- and single-layered BN nanoribbons, mostly terminated with zigzag edges, can be produced under unwrapping multiwalled BN nanotubes through plasma etching. The interesting stepwise unwrapping and intermediate states were observed and analyzed. Opposed to insulating primal tubes, the nanoribbons become semiconducting due to doping-like conducting edge states and vacancy defects, as revealed by structural analyses and ab initio simulations. This study paves the way for BN nanoribbon production and usage as functional semiconductors with a wide range of applications in optoelectronics and spintronics.
Wei XL, Wang MS, Bando Y, Golberg D
. Post-Synthesis Carbon Doping of Individual Multiwalled Boron Nitride Nanotubes via Electron-Beam Irradiation
. Journal of the American Chemical Society. 2010;132:13592-13593.
Wei XL, Wang MS, Bando Y, Golberg D
. Tensile Tests on Individual Multi-Walled Boron Nitride Nanotubes
. Advanced Materials [Internet]. 2010;22:4895-+. 访问链接Abstract
Tensile loading and pullouts of individual multi-walled BNNTs were studied for the first time by in-situ tests in the integrated HRTEM-AFM setup. Most important mechanical parameters, such as the ultimate tensile strength and strain, maximum sustainable load and the Young's modulus of tubes, were measured. Under parallel HRTEM observations the measured mechanical parameters were correlated to experimental conditions and tube structures.
Golberg D, Bando Y, Huang Y, Xu Z, Wei XL, Bourgeois L, Wang MS, Zeng HB, Lin J, Zhi CY
. Recent Advances in Boron Nitride Nanotubes and Nanosheets
. Israel Journal of Chemistry [Internet]. 2010;50:405-416. 访问链接Abstract
Herein the recent experiments performed by the authors on fabricated multi walled BN nanotubes and monoatomic BN graphene like nanosheets are reviewed The re suits are presented in several sections namely (i) method for high yield synthesis of thin, defect free BN nanotubes of only a few layers, with external diameters below 10 nm, (ii) verification of BN nanotube piezoelectrical behavior and its electrically induced thermal decomposition under combined resistive heating and electrical charging in a transmission electron microscope, (iii) the first direct measurements of the true tensile strength and Young's modulus of BN nanotubes, using newly developed nanotensile tests inside an electron microscope, the measured values were found to be similar to 30 GPa and similar to 900 GPa, respectively, and (iv) diverse kinetic processes taking place within the prepared monoatomic BN sheets (so called "white graphenes") affiliated with intensive knock on B and N atom displacements under high energy electron beam irradiation in an aberration corrected medium voltage high resolution transmission electron microscope
Gao YB, Wang Y, Wang JY, Xu SY, Wei XL, Wang MS, Li Y, Peng LM
. Thermoelectric Measurement of Multi-Walled Carbon Nanotube Bundles by Using Nano-Probes
. Journal of Nanoscience and Nanotechnology [Internet]. 2010;10:4985-4991. 访问链接Abstract
We report here a method for measurement of thermoelectric power of quasi-one dimensional nano-materials with a simple platform, where individual nanomaterial is assembled with nano-probes in a scanning electron microscope. This approach allows repeated manipulation and thermoelectric measurement of the same loaded nanosample with adjustable number of individual nanotubes or nanowires. It also allows assembly of multiple samples on one measurement stage. For multi-walled carbon nanotube bundles, we have observed a weak trend that, when the number of individual tubes in a bundle varies from ten millions to around a hundred thousand, the thermoelectric power almost remains at around 10 mu V/K. When the tube number in the bundle is further reduced, the up-limit of the thermoelectric power gradually increases to a value near 20 mu V/K.