The Influence of C2H2 Flow Rate on the Composition, Structural and Properties of the Ni/α-C:H Films Deposited by FCVA

2016 ◽  
Vol 852 ◽  
pp. 1132-1139
Author(s):  
Han Zhou ◽  
Qing Yan Hou ◽  
Tian Qing Xiao ◽  
Bin Liao ◽  
Xian Ying Wu ◽  
...  

Nickel/carbon nanocomposite films with different C2H2 flow rate were deposited by filtered cathodic vacuum arc (FCVA) device. The composition and nanostructure of the films were investigated by X-ray diffraction (XRD), Raman scattering spectroscopy, X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The grain size increase from 8.7 nm at the C2H2 flow rate of 10 sccm to the maximum of 11.5 nm at 30 sccm, after that it decrease. The mean phase separation is in the range of 0.2-2.6 nm. The hardness of 21.6 Gpa was obtained at 50sccm.

2007 ◽  
Vol 14 (05) ◽  
pp. 891-897
Author(s):  
YAOHUI WANG ◽  
XU ZHANG ◽  
YUANZHI XU ◽  
XIANYING WU ◽  
HUIXING ZHANG ◽  
...  

Nanocomposite nc-TiC / a-C : H films have been deposited via filtered cathodic vacuum arc technique, employing Ti target and C 2 H 2 gas as material precursors. The composition and nanostructure of film, correlated to mechanical and tribological properties of film, are varied by changing C 2 H 2 flow rate and filter coil current. Glancing angle X-ray diffraction has been used to show that salient TiC (111) peak exists in film with grain size of order of 8–10 nm, as a function of filter coil current. Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) investigations demonstrate that the nc-TiC / a-C : H films mainly contain nanocrystalline graphite and sp2-bonded carbon, both as a function of C 2 H 2 flow rate. Mechanical tests confirm that the nc-TiC / a-C : H films possess superior hardness of 33.9 GPa and elastic modulus of 237.6 GPa.


2008 ◽  
Vol 15 (06) ◽  
pp. 781-786 ◽  
Author(s):  
KUI ZHOU ◽  
XIANYING WU ◽  
XU ZHANG ◽  
LIZHAO QIN ◽  
BIN LIAO

Nanocomposite nc - ZrCN / a - C : H(N) films were prepared by filtered cathodic vacuum arc technique using the C 2 H 2 and N 2 gas as the precursor. The effect of the C 2 H 2 and N 2 flow rate on the microstructure, internal stress, phase composition, and mechanical properties of nanocomposite nc - ZrCN / a - C : H(N) films has been investigated by glancing incidence X-ray diffraction (GIXRD), surface profiler, and X-ray photoelectron spectroscopy(XPS). It was revealed that the C 2 H 2 and N 2 flow rate affected the structure, Zr content, and internal stress of the films significantly. Furthermore, XRD pattern indicated the presence of the ZrCN crystalline grains in the range of 3–10 nm, and the deconvolution results for XPS spectra showed that the film mainly was constituted by Zr – C , C = C (sp2) and C – C (sp3) bonds.


2009 ◽  
Vol 16 (02) ◽  
pp. 265-270 ◽  
Author(s):  
LIKUN PAN ◽  
HAIBO LI ◽  
ZHUO SUN ◽  
CHANGQING SUN

Cu , Al , and Ti films of ~ 10 nm thickness were deposited on porous silicon (PS) at room temperature using Filtered Cathodic Vacuum Arc system and annealed at 800°C for 10 min in vacuum. The PS layers were obtained by anodization of Si wafer. X-ray photoelectron spectroscopy, photoluminescence (PL), photo-absorption (PA), and X-ray diffraction studies revealed that before annealing just Cu -deposited sample exhibited PL blueshift, PA redshift, and Si -2p level shift due to the Cu diffusion at the surface of PS. While after annealing, Cu - and Ti -deposited samples exhibited obvious PA redshift and Si -2p level shift, which arise from the crystal field variation due to the formation of Cu / Ti silicides at the surface as well as the conduction electronic transportation.


2000 ◽  
Vol 614 ◽  
Author(s):  
Hao Wang ◽  
S.P. Wong ◽  
W.Y. Cheung ◽  
N. Ke ◽  
M.F. Chiah ◽  
...  

ABSTRACTNanocomposite Co-C thin films of about 15 nm thick were prepared by pulsed filtered vacuum arc deposition. The films were characterized by x-ray photoelectron spectroscopy, non-Rutherford backscattering spectrometry, x-ray diffraction, magnetic force microscopy and magnetic measurements. The as-deposited films were amorphous. After annealing at 350°C for one hour in vacuum (< 10−3 Pa), the films were found to consist of nanocrystalline Co grains encapsulated in carbon. The superparamagnetism of the annealed Co36C64 film was demonstrated by the measurement of DC susceptibility and magnetic hysteresis using a SQUID magnetometer. The superparamagnetic relaxation blocking temperature was marked to be about 12K by the peak of the zero-field-cooled magnetization under a field of 100 Oe. The magnetic properties of these annealed granular Co-C films transform from superparamagnetism to ferromagnetism when the Co concentration increases.


2019 ◽  
Vol 19 (6) ◽  
pp. 3210-3217
Author(s):  
Jing Yang ◽  
Wang-Qing Fan ◽  
Ruihua Mu ◽  
Yamei Zhao

A novel Pd/SiO2 inorganic–organic composite material was developed for the selective separation of H2 from a mixture of H2 and CO2. Its thermal stability and microstructure calcined under N2 atmosphere were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and N2 sorption–desorption measurements. Pd element in Pd/SiO2 gel material exists in PdCl2 form, calcination at 350 °C can result in the complete transformation of Pd2+ to metallic Pd0. With the increase of calcination temperature, the hydrophobic Si–CH3 bands decreased in intensity. The residue of Pd/SiO2 material calcined at 800 °C was mainly composed of Si–O–Si, metallic Pd0, CSi4 and some elemental C0. The mean pore size, BET specific surface area and total pore volume of the as-prepared Pd/SiO2 material calcined at 350 °C was about 2.26 nm, 417.35 m2 g−1 and 0.288 m3 g−1, respectively. The mean H2 and CO2 permeances of the corresponding Pd/SiO2 membrane were 9.90×10−6 and 9.10×10−7 mol m−2 Pa−1 s−1, respectively, when operating at 200 °C and a pressure difference of 0.3 MPa. After the steam exposure at 200 °C for 168 h, the H2 permeance decreased by 3.23% while the H2/CO2 permselectivity increased by 2.50%.


Author(s):  
C. Muratore ◽  
A. A. Voevodin ◽  
J. J. Hu ◽  
J. S. Zabinski

A hybrid magnetron sputtering/pulsed laser deposition process was used to grow nanocrystalline yttria stabilized zirconia (YSZ) embedded in an amorphous YSZ/metal matrix. This nanocomposite design reduced friction and improved the toughness of YSZ. Films containing both silver and molybdenum exhibited friction coefficients between 0.2 and 0.4 in air (40% relative humidity) against silicon nitride balls at temperatures between 25° C and 700 °C. Additional solid lubricants reduced the friction coefficient to &lt;0.2 for over 10000 cycles at all temperatures. A multilayer film architecture was developed to further enhance the lifetime of the adaptive coatings. Electron microscopy, x-ray diffraction and x-ray photoelectron spectroscopy were used to correlate adaptive behavior at different temperatures to the composition and structure of the films.


2005 ◽  
Vol 885 ◽  
Author(s):  
Jin-Bao Wu ◽  
Yin-Wen Tsai ◽  
Chin-Te Shih ◽  
Mei-Yi Li ◽  
Ming-Sheng Leu ◽  
...  

ABSTRACTFor the purpose of developing the corrosion-resistant and low-cost metallic bipolar plates for direct methanol fuel cell (DMFC), Ti mesh, stainless steel and Si(100) were coated with TiN by using the filtered cathodic vacuum arc system (FCVA). These TiN films have received considerable attention because of its high anti-corrosion behavior and low contact-resistance. In order to improve the corrosion protective ability of TiN films and decrease pinholes of coating, growth modifications such as thickness of the coatings and bias applied to substrates have also been carried out. The microstructures and composition of TiN film were identified by the instrumental analyses such as scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The corrosion behavior of TiN coatings was studied in 0.5 M H2SO4 solutions by using potentiodynamic polarization method. The DC bias of −150 V was applied to the substrates to achieve a dense structure of approximately 400 nm coating of TiN, so that good corrosion protection of the Ti mesh and stainless steel substrates can be achieved. The TiN coating on stainless steel exhibited excellent corrosion behavior especially in lower corrosion current than 2×10−7 A/cm2.


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