Direct existence to suggest activity of copper ions surface diffusion on nanowire in growth process

2019 ◽  
Vol 33 (21) ◽  
pp. 1950249
Author(s):  
Yota Mabuchi ◽  
Norhana Mohamed Rashid ◽  
Jian Bo Liang ◽  
Naoki Kishi ◽  
Tetsuo Soga
Keyword(s):  
Copper Oxide ◽  
Surface Diffusion ◽  
Flow Rate ◽  
Atmospheric Pressure ◽  
Growth Process ◽  
Copper Ions ◽  
Vertical Direction ◽  
Copper Sheet ◽  
Oxide Nanowires ◽  
Cu Substrate

As regards the copper oxide nanowire growth process, our experiment was consistent with the proposal of copper ions surface diffusion on a nanowire. Simply in the atmospheric pressure it is possible to synthesize CuO nanowires by annealing a copper sheet. Under a general copper oxide nanowires occurring condition, pouring the flow rate of a slight amount of air into an enclosed electric furnace in the atmospheric pressure, copper oxide nanowires adhering copper particles were synthesized on copper sheet successfully. In the growth process of the CuO wire, when the Cu substrate was heated in the air, stresses caused grain boundaries of Cu2O and CuO layers in the Cu substrate. Ultimately Cu ions formed a wire tip diffusing on the surface of a CuO wire in the vertical direction to the top surface of the CuO layer, while assembling to the tip. In this report, we describe characteristics of the structure of the CuO nanowire obtained by lowering the air flow rate.

On the growth of copper oxide nanowires by thermal oxidation near the threshold temperature at atmospheric pressure

2021 ◽  
pp. 161130
Author(s):  
Calin Constantin Moise ◽  
Laura-Bianca Enache ◽  
Veronica Anastasoaie ◽  
Oana Andreea Lazar ◽  
Geanina Valentina Mihai ◽  
...  
Keyword(s):  
Copper Oxide ◽  
Thermal Oxidation ◽  
Atmospheric Pressure ◽  
Threshold Temperature ◽  
Oxide Nanowires

Processing and Characterization of Amorphous Copper Oxide Thin Films Prepared by Reactive Magnetron Sputtering

2018 ◽  
Vol 775 ◽  
pp. 238-245 ◽  
Author(s):  
Thitinai Gaewdang ◽  
Ngamnit Wongcharoen
Keyword(s):  
Thin Films ◽  
Low Temperature ◽  
Magnetron Sputtering ◽  
Copper Oxide ◽  
Flow Rate ◽  
Localized States ◽  
Positive Sign ◽  
Variable Range Hopping ◽  
Variable Range ◽  
Deposited Films

In this paper, copper oxide (CuOx) thin films with amorphous phase were prepared on glass substrates by reactive dc magnetron sputtering. The influence of the flow rate of O2 on the structural, optical and electrical properties of the as-deposited films was systematically studied. XRD revealed that the as-deposited films remained amorphous in the whole range of adjusted oxygen flow rate. Surface morphology and nanoparticle size of the films were observed by AFM. Electrical resistivity and Hall effect measurements were performed on the films with van der Pauw configuration. The positive sign of the Hall coefficient confirmed the p-type conductivity in all studied films. From temperature-dependent electrical conductivity of the films prepared at R(O2) of 1.5 sccm, it was show that three types of behavior can be expected, nearest-neighbor hopping at high temperature range (200-300 K), the Mott variable range hopping at low temperature (110-190 K) and Efros-Shklovskii variable range hopping at very low temperature (65-100 K). Some important parameters corresponding to Mott-VRH and ES-VRH like density of localized states near the Fermi level, localization length, degree of disorder, hopping distance and hopping energy were determined. These parameters would be helpful for optimizing the performance of photovoltaic applications.

Facile growth of centimeter-sized single-crystal graphene on copper foil at atmospheric pressure

2015 ◽  
Vol 3 (15) ◽  
pp. 3530-3535 ◽  
Author(s):  
Jing Li ◽  
Xuan-Yun Wang ◽  
Xing-Rui Liu ◽  
Zhi Jin ◽  
Dong Wang ◽  
...  
Keyword(s):  
Single Crystal ◽  
Flow Rate ◽  
Atmospheric Pressure ◽  
Copper Foil ◽  
Gas Flow ◽  
Gas Flow Rate ◽  
Single Crystalline ◽  
Slowing Down ◽  
Cu Foil

By mildly oxidizing Cu foil and slowing down the gas flow rate, centimeter-sized single-crystalline graphene was grown on Cu at atmospheric pressure.

Studying of Plasma- Polymerized Pyrrole at Variable Gas Flow Rates Via Plasma Jet

2021 ◽  
Vol 19 (48) ◽  
pp. 44-51
Author(s):  
Saba Jawad Kadhem
Keyword(s):  
Flow Rate ◽  
Atmospheric Pressure ◽  
Gas Flow ◽  
Flow Characteristics ◽  
Atmospheric Pressure Plasma ◽  
Optical Emission ◽  
Plasma Jet ◽  
Nonequilibrium Plasma ◽  
Nano Particles ◽  
Vis Spectroscopy

     In this manuscript has investigated the synthesis of plasma-polymerized pyrrole (C4H5N) nano-particles prepared by the proposed atmospheric pressure nonequilibrium plasma jet through the parametric studies, particularly gas flow rate (0.5, 1 and 1.5 L/min). The plasma jet which used operates with alternating voltage 7.5kv and frequency 28kHz. The plasma-flow characteristics were investigated based on optical emission spectroscopy (OES). UV-Vis spectroscopy was used to characterize the  oxidization  state for polypyrrole. The major absorption appears around 464.1, 449.7 and 435.3  nm at the three flow rate of argon gas. The chemical composition and structural properties of the contained samples which synthesized at 0.5 L/min as a argon flow rate were analyzed by scanning electron microscopy (SEM), Fourier transformation infrared spectroscopy (FTIR), Raman spectroscopy and X-ray diffraction (XRD). SEM point to a uniform distribution of polypyrrole (PPY) nanoparticles matrix. XRD technique showed a semicrystalline pattern for PPY)thin film. It is expected, that the high-quality plasma polymer grown by atmospheric pressure plasma jet method contributes to serving as conducting materials.

scholarly journals Fabrication of temperature sensor based on copper oxide nanowires grown on titanium coated glass substrate

2018 ◽  
Vol 36 (3) ◽  
pp. 460-468 ◽  
Author(s):  
Ali A. Aljubouri ◽  
Abdulqader D. Faisal ◽  
Wafaa K. Khalef
Keyword(s):  
Copper Oxide ◽  
Temperature Sensor ◽  
Glass Substrate ◽  
Physical Vapor Deposition ◽  
Copper Film ◽  
High Sensitivity ◽  
Infrared Thermal Imaging ◽  
Oxide Nanowires ◽  
Vapor Deposition Technique ◽  
Physical Vapor Deposition Technique

AbstractSingle phase, adherent films of copper oxide nanowires (CuO NWs) were successfully grown on a glass substrate. Titanium nanofilm was pre-coated on the glass substrate to assist the growth of a layer adherent to the substrate. The copper film of 1.5 μm thickness was deposited via physical vapor deposition technique followed by thermal oxidation in air at various temperatures for 4 h. The product was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet-visible (UV-Vis) and Fourier transformation infrared (FT-IR) spectroscopy to find the crystal structure, morphology, phases, and optical properties of the deposited films. The CuO NWs film with 60% transmittance at wavelengths greater than 800 nm was obtained. It can be used as an infrared thermal imaging filter and in optoelectronic devices. The fabricated temperature sensor exhibited high sensitivity in the temperature range of 20 °C to 180 °C.

Spectroscopic Studies of Magnetron Sputtering Plasma Discharge in Cu/O2/Ar Mixture for Copper Oxide Thin Film Fabrication

2015 ◽  
Vol 73 (1) ◽  
Author(s):  
Jia Wei Low ◽  
Nafarizal Nayan ◽  
Mohd Zainizan Sahdan ◽  
Mohd Khairul Ahmad ◽  
Ali Yeon Md Shakaff ◽  
...  
Keyword(s):  
Thin Film ◽  
Copper Oxide ◽  
Flow Rate ◽  
Langmuir Probe ◽  
Oxygen Flow Rate ◽  
Oxygen Flow ◽  
Oxide Thin Film ◽  
Substrate Bias ◽  
Substrate Bias Voltage ◽  
Copper Oxide Thin Film

Magnetron sputtering plasma for the deposition of copper oxide thin film has been investigated using optical emission spectroscopy and Langmuir probe. The intensity of the light emission from atoms and radicals in the plasma were measured using optical emission spectroscopy (OES). Then, Langmuir probe was employed to estimate the plasma density, electron temperature and ion flux. In present studies, reactive copper sputtering plasmas were produced at different oxygen flow rate of 0, 4, 8 and 16 sccm. The size of copper target was 3 inches. The dissipation rf power, Ar flow rate and working pressure were fixed at 400 W, 50 sccm and 22.5 mTorr, respectively. Since the substrate bias plays an important role to the thin film formation, the substrate bias voltages of 0, -40, -60 and -100 V were studied. Based on OES results, oxygen emission increased drastically when the oxygen flow rate above 8 sccm. On the other hand, copper and argon emission decreased gradually. In addition, Langmuir probe results showed a different ion flux when substrate bias voltage was applied. Based on these plasma diagnostic results, it has been concluded that the optimized parameter to produce copper oxide thin film are between -40 to -60 V of substrate bias voltage and between 8 to 12 sccm of oxygen flow rate.

Performance Testing on Transonic Rotors

2010 ◽  
Vol 132 (08) ◽  
pp. 52-53
Author(s):  
Anthony J. Gannon ◽  
Garth V. Hobson
Keyword(s):  
Mach Number ◽  
Power Consumption ◽  
Flow Rate ◽  
Atmospheric Pressure ◽  
High Speed ◽  
Performance Testing ◽  
Test Machine ◽  
Naval Postgraduate School ◽  
Scale Down ◽  
Limit Power

This article discusses the performance testing of transonic rotors at the Turbopropulsion Laboratory at the Naval Postgraduate School. The Mach number is one of the most important parameters in the case of high-speed compressors. In order to limit power consumption in a test machine, the simplest change is to scale down the machine. A second concept to reduce the power consumption of the machine once it has been scaled down is to throttle the flow before the rotor rather than after it. As a high-speed rotor compresses the incoming air by around 1.4–1.6 times, the air leaving it is appreciably denser than that coming in. If one throttles upstream of the rotor, the exhaust air leaves the machine at atmospheric pressure, which means that the incoming air is below atmospheric pressure. With upstream throttling, care has to be taken to provide long enough ducting ahead of the test compressor to present as uniform as possible flow after the flow rate measuring nozzle.

scholarly journals Experimental Verification of Impact of Sprinkled Area Length on Heat Exchange Coefficient

2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Petr Kracik ◽  
Marek Balas ◽  
Martin Lisy ◽  
Jiri Pospisil
Keyword(s):  
Gas Phase ◽  
Flow Rate ◽  
Atmospheric Pressure ◽  
Tube Bundle ◽  
New Technology ◽  
Thin Liquid Film ◽  
Flow Mode ◽  
Heat Exchange Coefficient ◽  
Flowing Fluid ◽  
The Ideal

On a sprinkled tube bundle, liquid forms a thin liquid film, and, in the case of boiling liquid, the liquid phase can be quickly and efficiently separated from the gas phase. There are several effects on the ideal flow mode and the heat transfer from the heating to the sprinkling liquid. The basic quantity is the flow rate of the sprinkling liquid, but also diameter of the tubes, pipe spacing of the tube bundle, and physical state of the sprinkling and heating fluid. Sprinkled heat exchangers are not a new technology and studies have been carried out all over the world. However, experiments (tests) have always been performed under strict laboratory conditions on one to three relatively short tubes and behaviour of the flowing fluid on a real tube bundle has not been taken into account, which is the primary aim of our research. In deriving and comparing the results among the studies, the mass flow rate based on the length of the sprinkled area is used, thus trying to adjust the different length of the heat exchanger. This paper presents results of atmospheric pressure experiments measured on two devices with different lengths of the sprinkled area but with the same number of tubes in the bundle with same pitch and surface at a temperature gradient of 15/40°C, where 15°C is the sprinkling water temperature at the outlet of the distribution pipe and 40°C is the temperature of heating water entering the bundle.

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