scholarly journals High Brightness Negative Ion Sources with High Emission Current Density

2002 ◽  
Author(s):  
Vadim Dudnikov
2010 ◽  
Vol 97 (11) ◽  
pp. 113107 ◽  
Author(s):  
Chi Li ◽  
Yan Zhang ◽  
Mark Mann ◽  
David Hasko ◽  
Wei Lei ◽  
...  

IVESC 2012 ◽  
2012 ◽  
Author(s):  
Xiaoxia Wang ◽  
Min Zhang ◽  
Xianheng Liao ◽  
JirRun Luo ◽  
Qinglan Zhao ◽  
...  

2007 ◽  
Vol 121-123 ◽  
pp. 813-816
Author(s):  
C.X. Xu ◽  
X.W. Sun ◽  
Z.L. Dong ◽  
G.P. Zhu ◽  
Y.P. Cui

In this paper, field emission from ZnO was studied by morphological and electronic design. By fabricating ZnO into nanopin structure with sharp tip, we can obtain low threshold and high emission current density. By doping ZnO with gallium, we can lift up the Fermi level and increase the conductivity to enhance the field emission. The fabrication of nanostructures and analysis of field emission will be discussed.


2002 ◽  
Vol 73 (2) ◽  
pp. 989-991 ◽  
Author(s):  
V. Dudnikov ◽  
C. W. Schmidt ◽  
R. Hren ◽  
J. Wendt

2015 ◽  
Vol 36 ◽  
pp. 44-50 ◽  
Author(s):  
Pankaj M. Koinkar ◽  
Sandip S. Patil ◽  
Toshihiro Moriga ◽  
Mahendra A. More

Electrochemical synthesis of Polypyrrole (PPy) thin films on Sn substrates has been carried out under cyclic voltammetry (CV) mode. The structural, morphological and chemical properties of the as-synthesized PPy films were investigated using various characterization techniques like SEM, UV-Visible and FTIR. Furthermore, field emission (FE) behaviour of the PPy thin film emitter were carried out at base pressure of ~ 1×10-8 mbar and found to be interesting. The threshold field, required to draw emission current density of 1 μA/cm2, is observed to be 0.90 V/μm and very high emission current density of 12.87 mA/cm2 has been drawn at applied field of ~ 2.8 V/μm. The emission current stability investigated at preset values of 1, 10 and 100 μA/cm2 is observed to be fairly good over duration of more than three hours. The simplicity of the synthesis route coupled with the capability to deliver very high emission current density at relatively lower applied field make the PPy thin field emitter as a potential candidate for practical applications in field emission based devices


2015 ◽  
Vol 29 (06n07) ◽  
pp. 1540035 ◽  
Author(s):  
Kashmira Harpale ◽  
Mahendra A. More ◽  
Pankaj M. Koinkar ◽  
Sandip S. Patil ◽  
Kishor M. Sonawane

Polypyrrole (PPy) nanostructures have been synthesized on indium doped tin oxide (ITO) substrates by a facile electrochemical route employing cyclic voltammetry (CV) mode. The morphology of the PPy thin films was observed to be influenced by the monomer concentration. Furthermore, FTIR revealed formation of electrically conducting state of PPy. Field emission investigations of the PPy nanostructures were carried out at base pressure of 1×10-8 mbar . The values of turn-on field, corresponding to emission current density of 1 μA/cm2 were observed to be 0.6, 1.0 and 1.2 V/μm for the PPy films characterized with rod-like, cauliflower and granular morphology, respectively. In case of PPy nanorods maximum current density of 1.2 mA/cm2 has been drawn at electric field of 1 V/μm. The low turn on field, extraction of very high emission current density at relatively lower applied field and good emission stability propose the PPy nanorods as a promising material for field emission based devices.


2008 ◽  
Vol 1142 ◽  
Author(s):  
Feng Jin ◽  
Yan Liu ◽  
Scott A Little ◽  
Chris M Day

ABSTRACTWe have created a thermionic cathode structure that consists of a thin tungsten ribbon; carbon nanotubes (CNTs) on the ribbon surface; and a thin layer of low work function barium strontium oxide coating on the CNTs. This oxide coated CNT cathode was designed to combine the benefits from the high field enhancement factor from CNTs and the low work function from the emissive oxide coating. The field emission and thermionic emission properties of the cathode have been characterized. A field enhancement factor of 266 and a work function of 1.9 eV were obtained. At 1221 K, a thermionic emission current density of 1.22A/cm2 in an electric field of 1.1 V/μm was obtained, which is four orders of magnitude greater than the emission current density from the uncoated CNT cathode at the same temperature. The high emission current density at such a modest temperature is among the best ever reported for an oxide cathode.


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