scholarly journals Field Emission Properties of the Dendritic Carbon Nanotubes Film Embedded with ZnO Quantum Dots

2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Shu Zuo ◽  
Xin Li ◽  
Weihua Liu ◽  
Yongning He ◽  
Zhihao Xiao ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Quantum Dots ◽  
Zinc Oxide ◽  
Field Emission ◽  
Dendritic Structure ◽  
Emission Current ◽  
Field Emission Properties ◽  
Field Emission Current ◽  
New Type ◽  
The Common

Response on the effects of individual differences of common carbon nanotubes on the field emission current stability and the luminescence uniformity of cathode film, a new type of cathode film made of dendritic carbon nanotubes embedded with Zinc oxide quantum dots is proposed. The film of dendritic carbon nanotubes was synthesized through high-temperature pyrolysis of iron phthalocyanine on a silicon substrate coated with zinc oxide nanoparticles. The dendritic structure looks like many small branches protrude from the main branches in SEM and TEM images, and both the branch and the trunk are embedded with Zinc oxide quantum dots. The turn-on field of the dendritic structure film is∼1.3 V/μm at a current of 2 μA, which is much lower than that of the common carbon nanotube film, and the emission current and the luminescence uniformity are better than that of the common one. The whole film emission uniformity has been improved because the multi-emission sites out from the dendritic structure carbon nanotubes cover up the failure and defects of the single emission site.

Field Emission Properties of Individual Carbon Nanotubes in Nanorobotic Manipulation and Electron-Beam-Induced Deposition

2004 ◽  
Vol 16 (6) ◽  
pp. 597-603 ◽  
Author(s):  
Fumihito Arai ◽  
◽  
Pou Liu ◽  
Lixin Dong ◽  
Toshio Fukuda ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Electron Beam ◽  
Field Emission ◽  
Emission Current ◽  
Emission Properties ◽  
Field Emission Properties ◽  
Field Emission Current ◽  
Multi Walled Carbon Nanotubes ◽  
Electron Beam Induced Deposition ◽  
Afm Cantilever

Field emission properties of individual multi-walled carbon nanotubes (MWNTs) were studied in nanorobotic manipulation and electron-beam-induced deposition (EBID). Nanotube emitters are constructed by picking up and assembling individual nanotubes on a commercially available atomic force microscope (AFM) cantilever or a tungsten probe. The relationship between field emission current and interelectrode distance was obtained by changing the distance between the tip of the nanotube emitter and the counterpart anode, which can be potentially applied as the principle for an approaching sensor to detect nanometer scale distance by observing field emission current in real time. Field emission current on a microampere scale from a CNT emitter was shown to be strong enough for EBID without obviously degrading emitters. Deposit topology was related to current density or the emitter shape, suggesting that information on emitter geometry could be obtained from EBID deposits. Energy dispersive X-ray spectrometry (EDS) analysis of deposits from W(CO)6showed that the tungsten mass exceeds 80% on the average among compositions. Much higher voltage may degrade the emitter, and saturated current may be used to adjust the emitter length in a controlled way.

CORRELATION BETWEEN ELECTRONIC STRUCTURES OF METAL-INTERCALATED SINGLE WALL CARBON NANOTUBES WITH THEIR FIELD EMISSION PROPERTIES

2005 ◽  
Vol 04 (spec01) ◽  
pp. 657-668
Author(s):  
YAN WANG ◽  
THANH N. TRUONG
Keyword(s):  
Carbon Nanotubes ◽  
Field Emission ◽  
Electronic Structures ◽  
Dft Method ◽  
Emission Current ◽  
Single Wall Carbon Nanotubes ◽  
Single Wall Carbon ◽  
Emission Properties ◽  
Field Emission Properties ◽  
Field Emission Current

The effects of various metal intercalations ( Li , Na and Be ) on the electronic structures and the field emission properties of single-wall carbon nanotubes (SWNT) were investigated using the periodic plane-wave DFT method. We found that intercalations of metal tend to shift the conductive characteristics of the SWNT from those of a semiconductor to those of a quasi-metallic conductor. The Fermi levels for all metal-intercalated in SWNT are moved toward the conduction band, induced by the charge transfer from the metal to the SWNT. Intercalations of Li and Na atoms increase the field emission current, whereas Be intercalation does not affect the field emission current due to the absence of high density of states around the Fermi level. The correlation between the electronic structures for the metal-intercalated nanowires with field emission properties is further discussed in light of the above results.

ZnO quantum dots decorated on optimized carbon nanotube intramolecular junctions exhibit superior field emission properties

RSC Advances ◽  
2016 ◽  
Vol 6 (65) ◽  
pp. 60877-60887 ◽  
Author(s):  
Chia-Te Hu ◽  
Jyh-Ming Wu ◽  
Jien-Wei Yeh ◽  
Han C. Shih
Keyword(s):  
Carbon Nanotubes ◽  
Quantum Dots ◽  
Zinc Oxide ◽  
Carbon Nanotube ◽  
Quantum Well ◽  
Field Emission ◽  
Emission Properties ◽  
Field Emission Properties ◽  
Zno Quantum Dots

Sensitive optical and superior field emission properties can be attained through the use of ZnO selective quantum well heterostructures grown on carbon nanotubes to fabricate carbon-zinc-oxide (CZO) nanotubes.

Influence of Cathode Size on Field Emission Properties of a Single Vertical Carbon Nanotube Material

2016 ◽  
Vol 723 ◽  
pp. 454-458 ◽  
Author(s):  
Li Guo Jing ◽  
He Qiu Zhang ◽  
Yu Qiu ◽  
Bing Yin ◽  
Li Zhong Hu
Keyword(s):  
Carbon Nanotube ◽  
Electric Field ◽  
Field Emission ◽  
Emission Current ◽  
Perfect Conductor ◽  
Current Increase ◽  
Emission Properties ◽  
Field Emission Properties ◽  
Field Emission Current ◽  
Constant Potential

In this work, we study the field emission properties of a single vertical carbon nanotube with cathode radius changing. The carbon nanotube is considered as purely perfect conductor, and the anode and cathode are modeled as discs. The radius of anode is kept as 24m, then the radius of cathode is changed from 24 m to 1 m. The emitter of that CNT consists of a hemispherical cap of 4 nm radius (r) on top of a cylinder height of 2 m (h). The distance from anode to cathode is w=h+20m. The overall surface area of the CNT and cathode are all grounded, and the anode plate has a constant potential value of 100 V. The distribution of potential and electric field, field emission current are obtained by simulating with the help of COMSOL Multiphysics 4.3b electrostatics module. We find that with cathode radius decrease, the electric field strength over the surface of carbon nanotube (CNT) strengthening and field emission current increase.

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