scholarly journals Electrochemical Characterisations to Elucidate the Pseudocapacitance Mechanisms of a CdS/WOx Nanocomposite Photoanode in Acidic Aqueous Electrolytes

2021 ◽  
Author(s):  
Daniel Jones ◽  
Charles W. Dunnill
Keyword(s):  
Electrochemical Impedance ◽  
Cadmium Sulphide ◽  
Ionic Species ◽  
Differential Capacitance ◽  
Dual Functional ◽  
Impedance Characteristics ◽  
Electrochemical Impedance Spectroscopy Data ◽  
New Generation ◽  
And Storage ◽  
Electrochemical Characterisations

<p>The electrochemical properties of a cadmium sulphide/tungsten(VI) sub-oxide (CdS/WO<sub>x</sub>) nanocomposite have been explored using aqueous solutions of acetic acid (pH 2.2) and acidified sodium acetate (pH 5.0), for the purpose of evaluating the origin of pseudocapacitance within the material. Through transient photocurrent response, galvanostatic charge/discharge and electrochemical impedance measurements, it was established that cation-intercalation phenomena were principally responsible for charge-accumulation in the composite and that the incorporation of ionic species into interstitial surface sites was more energetically favourable for protons than for sodium ions. The composite displayed promising capacitive performance in the tested electrolytes, exhibiting Coulombic efficiencies of up to 88% under galvanostatic cycling at 1.0 mA cm<sup>-2</sup> alongside a peak differential capacitance value of 560 mF cm<sup>-2</sup> during the discharge phase. From electrochemical impedance spectroscopy data it was further determined that whilst illumination by white light acted to decrease the series resistance of the photoanode, all other resistive and capacitive components of the impedance characteristics were affected negligibly by the irradiation. In combination, the investigations detailed herein provide an instructive resource for the development of CdS/WO<sub>x</sub> composites and the optimisation of electrolytes to improve the performance and chemical stability of such materials. Furthermore, the study serves as a potential foundation from which to advance the concept of integrating the conversion and storage of solar energy into a single dual-functional electrode, in turn facilitating a new generation of photo-supercapacitor devices.</p>

scholarly journals Electrochemical Characterisations to Elucidate the Pseudocapacitance Mechanisms of a CdS/WOx Nanocomposite Photoanode in Acidic Aqueous Electrolytes

2021 ◽  
Author(s):  
Daniel Jones ◽  
Charles W. Dunnill
Keyword(s):  
Electrochemical Impedance ◽  
Cadmium Sulphide ◽  
Ionic Species ◽  
Differential Capacitance ◽  
Dual Functional ◽  
Impedance Characteristics ◽  
Electrochemical Impedance Spectroscopy Data ◽  
New Generation ◽  
And Storage ◽  
Electrochemical Characterisations

<p>The electrochemical properties of a cadmium sulphide/tungsten(VI) sub-oxide (CdS/WO<sub>x</sub>) nanocomposite have been explored using aqueous solutions of acetic acid (pH 2.2) and acidified sodium acetate (pH 5.0), for the purpose of evaluating the origin of pseudocapacitance within the material. Through transient photocurrent response, galvanostatic charge/discharge and electrochemical impedance measurements, it was established that cation-intercalation phenomena were principally responsible for charge-accumulation in the composite and that the incorporation of ionic species into interstitial surface sites was more energetically favourable for protons than for sodium ions. The composite displayed promising capacitive performance in the tested electrolytes, exhibiting Coulombic efficiencies of up to 88% under galvanostatic cycling at 1.0 mA cm<sup>-2</sup> alongside a peak differential capacitance value of 560 mF cm<sup>-2</sup> during the discharge phase. From electrochemical impedance spectroscopy data it was further determined that whilst illumination by white light acted to decrease the series resistance of the photoanode, all other resistive and capacitive components of the impedance characteristics were affected negligibly by the irradiation. In combination, the investigations detailed herein provide an instructive resource for the development of CdS/WO<sub>x</sub> composites and the optimisation of electrolytes to improve the performance and chemical stability of such materials. Furthermore, the study serves as a potential foundation from which to advance the concept of integrating the conversion and storage of solar energy into a single dual-functional electrode, in turn facilitating a new generation of photo-supercapacitor devices.</p>

Electrochemical Impedance Characteristics of Sintered 7075 Aluminum Alloy Under Ssrt Condition

2013 ◽  
Vol 58 (2) ◽  
pp. 505-508 ◽  
Author(s):  
S. Sunada ◽  
N. Nunomura
Keyword(s):  
Aluminum Alloys ◽  
Complex Shape ◽  
Electrochemical Impedance ◽  
Ingot Metallurgy ◽  
View Point ◽  
Corrosion Properties ◽  
Electrochemical Tests ◽  
Impedance Characteristics ◽  
Polarization Test ◽  
Conventional Ingot

Powder metallurgy (P/M) process has the advantage of better formability to fabricate complex shape products without machining and welding. And recently this P/M process has been applied to the production of aluminum alloys. The P/M aluminum alloys thus produced also have received considerable interest because of their fine and homogeneous structure. Many papers have been published on the mechanical properties of the aluminum alloys produced by P/M process while there have been few on their corrosion properties from the view point of electrochemistry. In this experiment, therefore, two kinds of 7075 aluminum alloys prepared by the conventional ingot metallurgy (I/M) process and P/M process were used, I/M material is commercially available. and their corrosion behavior were investigated through the electrochemical tests such as potentiodynamic polarization test, slow rate strain tensile (SSRT) test and electrochemical impedance spectroscopy (EIS) measurement under SSRT test in the corrosion solution and the deionized water.

Graphene, related two-dimensional crystals, and hybrid systems for energy conversion and storage

Science ◽  
2015 ◽  
Vol 347 (6217) ◽  
pp. 1246501 ◽  
Author(s):  
Francesco Bonaccorso ◽  
Luigi Colombo ◽  
Guihua Yu ◽  
Meryl Stoller ◽  
Valentina Tozzini ◽  
...  
Keyword(s):  
Energy Conversion ◽  
Hybrid Systems ◽  
Dye Sensitized Solar Cells ◽  
Ionic Species ◽  
Two Dimensional ◽  
Storage Devices ◽  
Energy Needs ◽  
Energy Conversion And Storage ◽  
And Storage ◽  
Sensitized Solar Cells

Graphene and related two-dimensional crystals and hybrid systems showcase several key properties that can address emerging energy needs, in particular for the ever growing market of portable and wearable energy conversion and storage devices. Graphene’s flexibility, large surface area, and chemical stability, combined with its excellent electrical and thermal conductivity, make it promising as a catalyst in fuel and dye-sensitized solar cells. Chemically functionalized graphene can also improve storage and diffusion of ionic species and electric charge in batteries and supercapacitors. Two-dimensional crystals provide optoelectronic and photocatalytic properties complementing those of graphene, enabling the realization of ultrathin-film photovoltaic devices or systems for hydrogen production. Here, we review the use of graphene and related materials for energy conversion and storage, outlining the roadmap for future applications.

scholarly journals Pre-particle filtration and moisture control by efficient purging in various inlet and outlet of a 450 mm wafer front-opening unified pod

2015 ◽  
Vol 4 (2) ◽  
pp. 304 ◽  
Author(s):  
Bill Chiu ◽  
Shih-Cheng Hu ◽  
Angus Shiue ◽  
Yu-Yun Shiue ◽  
Zhe-Yu Huang
Keyword(s):  
Metal Corrosion ◽  
Native Oxide ◽  
Moisture Concentration ◽  
Contamination Control ◽  
Point Of Use ◽  
Particle Contamination ◽  
Film Cracking ◽  
New Generation ◽  
And Storage ◽  
Wafer Surfaces

The trend toward narrower line width in semiconductor manufacturing has made contamination control more and more important. The presence of moisture in wafer containers, such as front opening unified pods (FOUP), can lead to the native oxide residues growth, metal corrosion, and thin film cracking on wafer surfaces. Accordingly, decreasing contamination methods and improving factory efficiency are continuously researched. Single or multi-layer particulate shields on top of wafers in FOUPs may be used to prevent pollutant accumulation. In addition, point-of-use (POU) filtration may also been used to control particle contamination in FOUPs during wafer transformation and storage. The demand for stricter filtration led to the usage of 0.10 and 0.20 µm membranes to control the contamination. However, with the introduction of finer membranes end users may have concerns about deleterious remainders on wafers from undergoing filtration. There are a total of 25 pieces of wafers in the FOUP and the arrangement is from the bottom (wafer No. 1) to the top (wafer No. 25) with arising manner. Purging FOUPs to expel moisture vapors with Clean Dry Air (CDA) is one of the most popular methods.There was no previous research for investigating the purge performance on new-generation 450mm FOUPs. This research aims to study main factors influencing the performance of the purge system on 450mm FOUPs, including moisture concentration, CDA flow rate, and filter pressure.

Enrichment — the way to create a new generation of food products

2020 ◽  
pp. 36-40
Author(s):  
O.V. Sycheva ◽  
V.G. Kayshev
Keyword(s):  
Raw Materials ◽  
Caloric Intake ◽  
Food Products ◽  
Short Supply ◽  
Mass Consumption ◽  
Organoleptic Characteristics ◽  
Physiological Properties ◽  
Physico Chemical ◽  
New Generation ◽  
And Storage

The main dysnutrition of the Russian population is the excess of caloric intake over an indicator of the energy consumption level. One of the ways to solve this problem is the production of functional food products or enriched functional products. The essence of this is that only those micronutrients that are really in short supply should be used in the fortification of products. These should be products of mass consumption, and especially those that undergo refining, which results in the loss of micronutrients. The use of raw materials and ingredients only of natural (animal, vegetable, mineral) origin allows creating active complexes that qualitatively alter the physiological properties of the product and can affect many product characteristics and processes such as physico-chemical, structural, mechanical and organoleptic characteristics of the product, the processes of color formation, fermentation, oxidation, and storage capacity. However, sometimes a strong passion for enriching the product with useful macro- and micronutrients affects the taste characteristics. Therefore, when developing recipes and technologies for new-generation products, it is crucial that the enrichment of the product with important and necessary elements should not deteriorate the organoleptic characteristics. At the same time, it is essential to ensure the safety of products without compromising consumer properties. The diet should contain all the nutrients necessary for a person in sufficient quantities and balanced with each other in the most favorable proportions

Fog Computing and Virtualization

2018 ◽  
pp. 53-67
Author(s):  
Siddhartha Duggirala
Keyword(s):  
Cloud Computing ◽  
Fog Computing ◽  
Main Concern ◽  
Time Data ◽  
Human Machine Interaction ◽  
Processing Power ◽  
New Generation ◽  
And Storage ◽  
Virtual Services ◽  
Machine Interaction

The essence of cloud computing is moving out the processing from the local systems to remote systems. Cloud is an umbrella of physical/virtual services/resources easily accessible over the internet. With more companies adopting cloud either fully through public cloud or hybrid model, the challenges in maintaining a cloud capable infrastructure is also increasing. About 42% of CTOs say that security is their main concern for moving into cloud. Another problem, which is mainly problem with infrastructure, is the connectivity issue. The datacenter could be considered as the backbone of cloud computing architecture. Handling this new generation of requirements of volume, variety, and velocity in IoT data requires us to evaluate the tools and technologies. As the processing power and storage capabilities of the end devices like mobile phones, routers, sensor hubs improve, we can increase leverage these resources to improve your quality and reliability of services. Applications of fog computing is as diverse as IoT and cloud computing itself. What IoT and fog computing have in common is to monitor and analyse real-time data from network connected things and acting on them. Machine-to-machine coordination or human-machine interaction can be a part of this action. This chapter explores fog computing and virtualization.

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