Synthesis of Cu2O and ZnO Nanowires and their Heterojunction Nanowires by Thermal Evaporation: A Short Review

2014 ◽  
Vol 71 (5) ◽  
Author(s):  
Muhammad Arif Khan ◽  
Samsudi Sakrani ◽  
Syahida Suhaima ◽  
Yussof Wahab ◽  
Rosnita Muhammad
Keyword(s):  
Physical Vapor Deposition ◽  
Thermal Evaporation ◽  
Chemical Properties ◽  
High Sensitivity ◽  
Short Review ◽  
Zno Nanowires ◽  
Oxide Semiconductor ◽  
The Individual ◽  
Photovoltaic Solar Cells ◽  
Physical And Chemical

One dimensional metal oxide semiconductor nanowires of copper (I) oxide (Cu2O), zinc oxide (ZnO), and their heterojunction nanowires possess remarkable physical and chemical properties. ZnO and Cu2O areattractive because the metals are abundant on earth, inexpensive, nontoxic.Moreover, these oxides have useful optical and electrical properties suitable for a wide variety of electrical devices, because their electrical conduction can be predictably controlled by doping. We here restrict the disscussion using a Hot Tube Vacuum Thermal Evaporation. The NWs in these devices will be studied by physical vapor deposition known as vapor-liquid-solid (VLS). Therefore, we explore conventional methods, particularly the VLS of growing ZnO and Cu2O nanowires which are assisted by the catalyst.  In this short review, we report the individual and combined (Cu2O/ZnO) junction nanowires by PVD method.  The main advantages of these composite nanowires are the natural p-n characteristics, the broad light absorption, the high sensitivity to humidity changes, and the fast dynamic response. The combination of all characteristics offered by Cu2O/ZnO nanowires can enable the fabrication of diverse sensing devices, and photovoltaic solar cells.

scholarly journals Research Progress of Gas Sensing Performance of 2D Hexagonal WO3

2021 ◽  
Vol 9 ◽  
Author(s):  
Yueqi Li ◽  
Qin Zhou ◽  
Shoubing Ding ◽  
Zhimin Wu
Keyword(s):  
Gas Sensing ◽  
Low Cost ◽  
Chemical Properties ◽  
High Sensitivity ◽  
Oxide Semiconductor ◽  
Research Progress ◽  
Research Directions ◽  
Sensor Field ◽  
Sensitivity And Selectivity ◽  
Physical And Chemical

Metal oxide semiconductor gas sensing materials have attracted great research interest in the gas sensor field due to their outstanding physical and chemical properties, low cost, and easy preparation. Among them, two-dimensional hexagonal tungsten trioxide (2D h-WO3) is especially interesting because of its high sensitivity and selectivity to some gases. We firstly introduce the characteristics of 2D h-WO3 gas sensing materials and discuss the effects of microstructure, oxygen vacancy, and doping modification on the gas sensing properties of 2D h-WO3 mainly. Finally, we explore the application of 2D h-WO3 gas sensing materials and propose some research directions.

Fabrication of ZnO Bridging Nanowire Device by a Single-Step Chemical Vapor Deposition Method

2008 ◽  
Vol 1144 ◽  
Author(s):  
Yanbo Li ◽  
Ippei Nagatomo ◽  
Ryohei Uchino ◽  
Ichiro Yamada ◽  
Jean-Jacques Delaunay
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Gas Sensing ◽  
Gold Catalyst ◽  
Chemical Vapor ◽  
High Sensitivity ◽  
Single Step ◽  
Zno Nanowires ◽  
Oxide Semiconductor ◽  
Chemical Vapor Deposition Method

ABSTRACTZnO nanowires are directly integrated into a working device by a single-step chemical vapor deposition (CVD) method. Gold catalyst is patterned on a quartz glass substrate using a comb-shaped shadow mask and then ZnO is grown on the patterned substrate by CVD. Thick ZnO layers formed on the gold-patterned areas serve as native electrodes. Ultra-long (˜100 μm) ZnO nanowires grown across the gap between the ZnO electrodes and the nanowires serve as the sensing elements of the device. The device exhibits high sensitivity and fast response to UV illumination in air. Our method can be used to fabricate other metal oxide semiconductor bridging nanowire devices, which have promising applications in photodetection and gas sensing.

scholarly journals Preparation and Properties of Composite PAN/PANI Membranes

2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
Beata Fryczkowska ◽  
Zofia Piprek ◽  
Marta Sieradzka ◽  
Ryszard Fryczkowski ◽  
Jarosław Janicki
Keyword(s):  
Surface Morphology ◽  
Transport Properties ◽  
Chemical Properties ◽  
High Sensitivity ◽  
Sensory Properties ◽  
Inversion Method ◽  
Phase Inversion Method ◽  
Physical And Chemical ◽  
Polyacrylonitrile Solution ◽  
Interesting Solution

The methods of modifying PAN membranes have been known and used for many years. An interesting solution seems to be to give the sensory properties to this type of membranes. This paper presents the results of research on the method of obtaining PAN/PANI membranes using phase inversion method from a solution in DMF, following two methods: (1) dissolving both polymers (PAN and PANI) and then coagulating in water or in an aqueous solution of CSA and (2) forming the membranes from polyacrylonitrile solution and coagulation in water, followed by coating of CSA with a solution of TFE. The membranes obtained as a result of the experiment were tested for physical and chemical properties, transport properties, surface morphology, degree of dispersion of composite components, and sensitivity to the presence of dilute acids and bases. FTIR microspectroscopy and scanning electron microscopy were used to study the surface morphology. The sensory properties of membranes that are inherently colored were determined visually and by UV-Vis spectrophotometry. Furthermore, when choosing the method of membrane forming, we can obtain membranes with good physical and chemical and transport properties or ones characterized by high sensitivity to the pH of the solution.

Isoprene and Rubber. XVII. The Fractionation of Balata

1930 ◽  
Vol 3 (3) ◽  
pp. 511-515
Author(s):  
H. Staudinger ◽  
H. F. Bondy
Keyword(s):  
Molecular Weight ◽  
Natural Products ◽  
High Molecular Weight ◽  
Homologous Series ◽  
Chemical Properties ◽  
Uniform Size ◽  
Gutta Percha ◽  
Synthetic Materials ◽  
The Individual ◽  
Physical And Chemical

Abstract On the basis of earlier experiments with synthetic materials, compounds of high molecular weight are not composed of a single substance, but consist of a mixture of homologous polymers. The individual members of a polymeric homologous series differ very little in physical and chemical properties, and therefore a mixture of polymeric homologous products such as is obtained in the polymerization of the monomer cannot as a rule be decomposed into simple compounds by means of solvents, but merely into mixtures of products of low and high molecular weight. Such separations have been carried out, for example, in the case of polyvinylace-tates, polystyrols, polyindenes, polyanetholes, and polyethyleneoxides. On the basis of these experiments it was assumed that natural products of high molecular weight likewise consist of a mixture of polymeric homologs. Thus purified rubber, for example, according to our views is not such a completely homogeneous hydrocarbon that all the molecules have the same length, but consists of a mixture of perhaps 100 or more polymeric homologs. Pummerer's decomposition of rubber into sol,- and gel-rubber, according to our experiments, is due to the fact that rubber consists of easily soluble polyprenes and difficultly soluble polyprenes, all belonging to the same polymeric homologous series. Of course there is the possibility that, in forming compounds of high molecular weight, nature produced primary molecules of uniform size, and that the mixture of polymeric homologs was formed only later through decomposition. In that case the natural products would differ in constitution from the synthetic material. They would not be polymerically uniform but completely uniform compounds in the sense of classical organic chemistry. The fact that in life processes methods are possible which we cannot realize in the laboratory is well known. Such a finding would not, of course, contradict our former view that natural products, such as rubber and balata, are of high molecular weight in the sense of classical structural chemistry. Our former work has indicated a similar structure for rubber and gutta-percha. Here it is simply a question whether or not the macromolecules of these natural products have a uniform length. In order to reach a decision, we first of all investigated balata, since it is prepared pure more easily than rubber. It was made from balata latex which was supplied to us through the courtesy of the management of the Norddeutsche Seekabelwerke, Nordenham." The balata thus obtained is a flocculent, cellulose-like mass, which looks like gutta-percha and crystallizes like it.

scholarly journals In-situ Detection Method for Microplastics in Water by Polarized Light Scattering

2021 ◽  
Vol 8 ◽  
Author(s):  
Tong Liu ◽  
Shijun Yu ◽  
Xiaoshan Zhu ◽  
Ran Liao ◽  
Zepeng Zhuo ◽  
...  
Keyword(s):  
Light Scattering ◽  
Scattered Light ◽  
Polarized Light ◽  
Chemical Properties ◽  
Future Application ◽  
Physical And Chemical Properties ◽  
The Individual ◽  
Physical And Chemical ◽  
And Chemical Properties

Microplastics (MPs) have become the widespread contaminants, which raises concerns on their ecological hazards. In-situ detection of MP in water bodies is essential for clear assessment of the ecological risks of MPs. The present study proposes a method based on polarized light scattering which measures the polarization parameters of the scattered light at 120° to detect MP in water. This method takes the advantage of in-situ measurement of the individual particles and the experimental setup in principle is used. By use of the measured polarization parameters equipped by machine learning, the standard polystyrene (PS) spheres, natural water sample, and lab-cultured microalgae are explicitly discriminated, and MP with different physical and chemical properties can be differentiated. It can also characterize the weathering of different MP and identify the specific type from multiple types of MP. This study explores the capability of the proposed method to detect the physical and chemical properties, weathering state and concentration of MP in water which promises the future application in water quality sensing and monitoring.

Use of Rejuvenators to Rejuvenate Asphalt Binders in RAP

2017 ◽  
Vol 737 ◽  
pp. 547-553
Author(s):  
Iva Krcmova ◽  
Petr Hyzl ◽  
Pavla Nekulova ◽  
Pavel Coufalik ◽  
Ondrej Dasek
Keyword(s):  
Asphalt Pavement ◽  
Asphalt Binder ◽  
Chemical Properties ◽  
Asphalt Binders ◽  
Reclaimed Asphalt Pavement ◽  
Reclaimed Asphalt ◽  
Aged Asphalt ◽  
Empirical Tests ◽  
The Individual ◽  
Physical And Chemical

With increased demand and limited aggregate and binder supply, hot mix asphalt (HMA) producers discovered that reclaimed asphalt pavement (RAP) is a valuable component in HMA. This paper is concerned with the current issue of higher using RAP (Reclaimed Asphalt Pavement) in asphalt mixtures for pavement wearing courses. It describes the effects of application of three types of rejuvenation additives on properties of aged asphalt binders made from a regular RAP. These rejuvenation additives restore the physical and chemical properties of aged binders. In addition, the aged asphalt binder with rejuvenators applied was subjected to a short-term laboratory aging using the RTFOT (Rolling Thin Film Oven Test). This method simulate aging asphalt binder during the manufacturing process and laying. To assess the binder properties, both the standard empirical tests and more advanced functional tests (dynamic shear rheometer and bending beam rheometer) have been performed. Last part of the paper provides an evaluation of the individual rejuvenation additives. Based on the results it can be concluded that a positive change in properties of aged asphalt binder after applying all the three rejuvenators has been proven.

High Sensitivity Humidity Sensor Based on ZnSnO3 Composite Nanocube

2013 ◽  
Vol 594-595 ◽  
pp. 872-876
Author(s):  
N.D. Md Sin ◽  
M.Z. Musa ◽  
M.H. Mamat ◽  
S. Ahmad ◽  
A. Abdul Aziz ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Humidity Sensor ◽  
Chemical Properties ◽  
High Sensitivity ◽  
Physical And Chemical Properties ◽  
Sensor Performance ◽  
Semiconducting Material ◽  
Physical And Chemical ◽  
And Chemical Properties

The performance of nanocomposites semiconducting material used as a sensor is very much depending upon physical and chemical properties of the material. In this paper we address sensitivity of ZnSnO3thin film deposited by hydrothermal deposition in terms of its behavior towards humidity variations. The electrical, optical and structural properties of ZnSnO3thin film deposit at different volume of solvent (50 ml and 70 ml) grown by novel deposition of ZnSnO3hydrothermal with low temperature 95°C are also reviewed. The sensor performance of ZnSnO3thin film prepared at 50 ml volume show high sensitivity towards humidity. Using FESEM it was noted that the nanocube of ZnSnO3thin films growth on ZnO template with the size of nanocube is 100 to 140nm by varying the volume of the solvent.

scholarly journals Application of Physical Vapor Deposition in Textile Industry

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Pamela Miśkiewicz ◽  
Iwona Frydrych ◽  
Agnieszka Cichocka
Keyword(s):  
Vapor Deposition ◽  
Textile Industry ◽  
Physical Vapor Deposition ◽  
Chemical Properties ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Knitted Fabrics ◽  
Textile Materials ◽  
Almost All ◽  
Physical And Chemical

AbstractCurrently, scientists are striving to produce innovative textile materials characterized by special properties. Therefore, attempts have been made to use physical and chemical vapor deposition techniques to modify the surface of textile materials, i.e., nonwovens, fabrics, and knitted fabrics. By using these techniques for modifying the basic materials, researchers have obtained textiles with novel properties, which are used in shielding materials, textronics, or clothing, as well as in specialized accessories. The PVD process can be applied for almost all materials. The physical vapor deposition process allows for obtaining layers of different thicknesses and with various physical and chemical properties. This article is a review of the latest state of the art on the use of various methods of physical vapor deposition in textiles destined for different purposes.

scholarly journals Ferroelastic Twinning in Minerals: A Source of Trace Elements, Conductivity, and Unexpected Piezoelectricity

Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 478
Author(s):  
Ekhard K. H. Salje
Keyword(s):  
Chemical Properties ◽  
Topological Defects ◽  
Short Review ◽  
Major Research ◽  
Wall Properties ◽  
Structural Deformations ◽  
Research Initiatives ◽  
Physical And Chemical ◽  
Future Work ◽  
And Chemical Properties

Ferroelastic twinning in minerals is a very common phenomenon. The twin laws follow simple symmetry rules and they are observed in minerals, like feldspar, palmierite, leucite, perovskite, and so forth. The major discovery over the last two decades was that the thin areas between the twins yield characteristic physical and chemical properties, but not the twins themselves. Research greatly focusses on these twin walls (or ‘twin boundaries’); therefore, because they possess different crystal structures and generate a large variety of ‘emerging’ properties. Research on wall properties has largely overshadowed research on twin domains. Some wall properties are discussed in this short review, such as their ability for chemical storage, and their structural deformations that generate polarity and piezoelectricity inside the walls, while none of these effects exist in the adjacent domains. Walls contain topological defects, like kinks, and they are strong enough to deform surface regions. These effects have triggered major research initiatives that go well beyond the realm of mineralogy and crystallography. Future work is expected to discover other twin configurations, such as co-elastic twins in quartz and growth twins in other minerals.

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