Combined x-ray photoelectron spectroscopy/ultraviolet photoelectron spectroscopy/field emission spectroscopy for characterization of electron-emission mechanism of diamond

Author(s):  
H. Yamaguchi ◽  
Y. Kudo ◽  
T. Masuzawa ◽  
M. Kudo ◽  
T. Yamada ◽  
...  
2005 ◽  
Vol 475-479 ◽  
pp. 3595-3598
Author(s):  
Lan Zhang ◽  
Hui Zhong Ma ◽  
Xue Xiang Li ◽  
Ning Yao ◽  
Bing Lin Zhang

Carbon nitride nanotubes (CN-NT) thin films were prepared on Ni-Cr coated glass substrate by microwave plasma enhanced chemical vapor deposition at a relatively low temperature of 600~650 °C. The morphology of the films were observed by scanning electron microscopy. The microstructure of the film were analyzed by x-ray photoelectron spectroscopy, x-ray diffraction, and Raman spectroscopy. The characteristics of field emission of CN-NT thin films were measured. Experimental results indicate that the film structure and properties of the field electron emission are related to flow ratio of N2 to CH4. When the flow ratio of N2 to CH4 was 3.3, the obtained film had a better field electron emission characteristics. The turn-on field of the film was 3.7 V/µm . The current density was 413.3 µA/cm2 at an electric field of 8 V/µm.


2003 ◽  
Vol 9 (4) ◽  
pp. 337-342 ◽  
Author(s):  
Gy. Vida ◽  
V.K. Josepovits ◽  
M. Győr ◽  
P. Deák

The changes of the work function (Φ) and the secondary electron emission (SEE) of oxygen covered polycrystalline tungsten occurring after ion sputtering and heat treatments have been investigated. The chemical composition was analyzed by X-ray photoelectron spectroscopy (XPS), and the electron emission properties by work function spectroscopy (WFS). We observed in what manner the chemical changes of the surface are reflected in the work function and SEE. The simultaneous change of Φ and SEE in the case of oxygen covered tungsten have been pointed out and a direct relationship between them can be supposed.


2012 ◽  
Vol 1406 ◽  
Author(s):  
Mikihiko Nishitani ◽  
Mutsumu Fukada ◽  
Yukihiro Morita ◽  
Masaharu Terauchi ◽  
Tessei Kurashiki ◽  
...  

ABSTRACTWe report the properties of MgO:Si film as a protective cathode material on the electrical discharge, and the electronic state of the outer-most surface on MgO:Si film characterized by helium Meta-stable De-excitation Spectroscopy (MDS) and that of several nanometer region from the surface evaluated by X-ray Photoelectron Spectroscopy (XPS). Both of the spectra are discussed focusing on the dependence upon the amount of Si in the MgO film for understanding discharge phenomena. The analyses of the experimental data imply that the discharge properties are not improved due to surface degradation with the increase of Si in MgO films. However, an in-situ discharge experiment, in which MgO:Si films are not exposed for the atmosphere after its deposition, shows that the introduction of Si up to about 1 atomic% has the potential to enhance the secondary electron emission coefficient.


Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1518
Author(s):  
Minsu Kim ◽  
Dabin Park ◽  
Jooheon Kim

Herein, Sb2Se3 and β-Cu2Se nanowires are synthesized via hydrothermal reaction and water evaporation-induced self-assembly methods, respectively. The successful syntheses and morphologies of the Sb2Se3 and β-Cu2Se nanowires are confirmed via X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), and field emission transmission electron microscopy (FE-TEM). Sb2Se3 materials have low electrical conductivity which limits application to the thermoelectric generator. To improve the electrical conductivity of the Sb2Se3 and β-Cu2Se nanowires, polyaniline (PANI) is coated onto the surface and confirmed via Fourier-transform infrared spectroscopy (FT-IR), FE-TEM, and XPS analysis. After coating PANI, the electrical conductivities of Sb2Se3/β-Cu2Se/PANI composites were increased. The thermoelectric performance of the flexible Sb2Se3/β-Cu2Se/PANI films is then measured, and the 70%-Sb2Se3/30%-β-Cu2Se/PANI film is shown to provide the highest power factor of 181.61 μW/m·K2 at 473 K. In addition, a thermoelectric generator consisting of five legs of the 70%-Sb2Se3/30%-β-Cu2Se/PANI film is constructed and shown to provide an open-circuit voltage of 7.9 mV and an output power of 80.1 nW at ΔT = 30 K. This study demonstrates that the combination of inorganic thermoelectric materials and flexible polymers can generate power in wearable or portable devices.


1992 ◽  
Vol 270 ◽  
Author(s):  
Haojie Yuan ◽  
R. Stanley Williams

ABSTRACTThin films of pure germanium-carbon alloys (GexC1−x with x ≈ 0.0, 0.2, 0.4, 0.5, 0.6, 0.8, 1.0) have been grown on Si(100) and A12O3 (0001) substrates by pulsed laser ablation in a high vacuum chamber. The films were analyzed by x-ray θ-2θ diffraction (XRD), x-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), conductivity measurements and optical absorption spectroscopy. The analyses of these new materials showed that films of all compositions were amorphous, free of contamination and uniform in composition. By changing the film composition, the optical band gap of these semiconducting films was varied from 0.00eV to 0.85eV for x = 0.0 to 1.0 respectively. According to the AES results, the carbon atoms in the Ge-C alloy thin film samples has a bonding configuration that is a mixture of sp2 and sp3 hybridizations.


2014 ◽  
Vol 34 (3) ◽  
pp. 841-849 ◽  
Author(s):  
M. Kanuchova ◽  
L. Kozakova ◽  
M. Drabova ◽  
M. Sisol ◽  
A. Estokova ◽  
...  

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