Capacitive Behavior of Single Gallium Oxide Nanobelt.
Ontology highlight
ABSTRACT:
SUBMITTER: Cai H
PROVIDER: S-EPMC5455499 | biostudies-other | 2015 Aug
REPOSITORIES: biostudies-other
Similar Datasets
Project description:Graphene oxide-wrapped amorphous copper vanadium oxide is fabricated through a template-engaged redox reaction followed by vacuum dehydration. This material exhibits high reversible capacity, excellent rate capability, and out standing high-rate cyclability. The outstanding performance is attributed to the fast capacitive charge storage and the in situ formed copper with enhanced electrical conductivity.
| S-EPMC5115307 | biostudies-literature
Project description:Our laboratory has previously revealed the use of metal-semiconductor-metal (MSM) varactors against malicious pulses, as well as completed the related verification and measurements of such a circuit. To improve the reliability of this protection module further, in this study, we deposited a gallium oxide (Ga2O3) thin film in between the Schottky contact electrode to manufacture a metal-oxide-semiconductor-oxide-metal (MOSOM) varactor. However, the thin-film quality and heterojunction interfaces will affect these fabricated varactors in various ways, such as the asymmetry threshold voltage to the variable capacitance characteristics. This study aims to address the issues associated with the inserted oxide thin film, as well as to determine how improvements could be obtained by using an oxygen furnace annealing process. As a result, the breakdown voltage of the MOSOM varactor was further promoted and a more robust anti-surge module was thus realized.
| S-EPMC7662979 | biostudies-literature
Project description:Capacitive deionization is a second-generation water desalination technology in which porous electrodes (activated carbon materials) are used to temporarily store ions. In this technology, porous carbon used as electrodes have inherent limitations, such as low electrical conductivity, low capacitance, etc., and, as such, optimization of electrode materials by rational design to obtain hybrid electrodes is key towards improvement in desalination performance. In this work, different compositions of mixture of reduced graphene oxide (RGO) and activated carbon (from 5 to 20 wt% RGO) have been prepared and tested as electrodes for brackish water desalination. The physico-chemical and electrochemical properties of the activated carbon (AC), reduced graphene oxide (RGO), and as-prepared electrodes (AC/RGO-x) were characterized by low-temperature nitrogen adsorption measurement, scanning electron microscope (SEM), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Fourier transform infra-red (FT-IR), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). Among all the composite electrodes, AC/RGO-5 (RGO at 5 wt%) possessed the highest specific capacitance (74 F g-1) and the highest maximum salt adsorption capacity (mSAC) of 8.10 mg g-1 at an operating voltage ∆E = 1.4 V. This shows that this simple approach could offer a potential way of fabricating electrodes of accentuated carbon network of an improved electronic conductivity that's much coveted in CDI technology.
| S-EPMC8144981 | biostudies-literature
Project description:There is much recent interest in graphene-based composite electrode materials because of their excellent mechanical strengths, high electron mobilities, and large specific surface areas. These materials are good candidates for applications in supercapacitors. In this work, a new graphene-based electrode material for supercapacitors was fabricated by anchoring carbon dots (CDs) on reduced graphene oxide (rGO). The capacitive properties of electrodes in aqueous electrolytes were systematically studied by galvanostatic charge-discharge measurements, cyclic voltammetry, and electrochemical impedance spectroscopy. The capacitance of rGO was improved when an appropriate amount of CDs were added to the material. The CD/rGO electrode exhibited a good reversibility, excellent rate capability, fast charge transfer, and high specific capacitance in 1 M H₂SO₄. Its capacitance was as high as 211.9 F/g at a current density of 0.5 A/g. This capacitance was 74.3% higher than that of a pristine rGO electrode (121.6 F/g), and the capacitance of the CD/rGO electrode retained 92.8% of its original value after 1000 cycles at a CDs-to-rGO ratio of 5:1.
| S-EPMC5245759 | biostudies-literature
Project description:The electrochemical behavior and electrodeposition of gallium was studied in a non-aqueous electrolyte comprising of gallium(iii) chloride and 1,2-dimethoxyethane (DME). Electrochemical quartz crystal microbalance (EQCM) and rotating ring disk electrode (RRDE) measurements indicate that reduction of gallium(iii) is a two-step process: first from gallium(iii) to gallium(i), and then from gallium(i) to gallium(0). The morphology and elemental composition of the electrodeposited layer were examined using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Metallic gallium was deposited as spheres with diameters of several hundred nanometers that were stacked on top of each other. X-ray photoelectron spectroscopy (XPS) revealed that each gallium sphere was covered by a thin gallium oxide shell. Electrochemical experiments indicated that these oxide layers are electrically conductive, as gallium can be electrodeposited and partially stripped on or from the layer of spheres below. This was further evidenced by simultaneous electrodeposition of gallium and indium, using indium as a tracer. Electrodeposition of gallium from an O2-containing electrolyte resulted in spheres with smaller diameters. This was due to the formation thicker oxide shells, through which diffusion of gallium atoms that were electrodeposited on the surface, was slower. The concentration of gallium adatoms on top of the gallium spheres to form a new sphere therefore reaches the critical concentration for nucleating a new gallium sphere sooner, leading to smaller spheres.
| S-EPMC8317176 | biostudies-literature
Project description:A common feature of many neuropsychiatric disorders is deficit in social behavior. In order to study mouse models for such disorders, several behavioral tests involving social interaction with other mice have been developed. While a precise annotation of rodent behavioral state is necessary for these types of experiments, manual annotation of rodent social behavior is time-consuming and subjective. Therefore, an automated system that can instantly and independently quantify the animal's social exploration is desirable. We developed a capacitive touch device for automated detection of direct social-exploration in a modified three-chamber social behavior test. In this device, capacitive sensors can readily detect nose-pokes and other direct physical touches from the rodent under investigation. In addition, a conductive barrier makes mouse behavioral output immediately available for real-time use, by sending data to a host computer via a custom Field-Programmable Gate Array (FPGA) platform. Our capacitive touch sensing device produced similar results to the manually annotated data, demonstrating the ability to instantly and independently analyze direct social-exploration of animals in a social behavior test. Compared to the manual annotation method, this capacitive touch sensing system can be used to instantaneously quantify direct social-exploration, saving significant amount of time of post-hoc video scoring. Furthermore, this low-cost method enhances the objectivity of data by reducing experimenter involvement in analysis.
| S-EPMC7479347 | biostudies-literature
Project description:A new technique is proposed for the activation of low temperature amorphous InGaZnO thin film transistor (a-IGZO TFT) backplanes through application of a bias voltage and annealing at 130?°C simultaneously. In this 'electrical activation', the effects of annealing under bias are selectively focused in the channel region. Therefore, electrical activation can be an effective method for lower backplane processing temperatures from 280?°C to 130?°C. Devices fabricated with this method exhibit equivalent electrical properties to those of conventionally-fabricated samples. These results are analyzed electrically and thermodynamically using infrared microthermography. Various bias voltages are applied to the gate, source, and drain electrodes while samples are annealed at 130?°C for 1?hour. Without conventional high temperature annealing or electrical activation, current-voltage curves do not show transfer characteristics. However, electrically activated a-IGZO TFTs show superior electrical characteristics, comparable to the reference TFTs annealed at 280?°C for 1?hour. This effect is a result of the lower activation energy, and efficient transfer of electrical and thermal energy to a-IGZO TFTs. With this approach, superior low-temperature a-IGZO TFTs are fabricated successfully.
| S-EPMC5057139 | biostudies-literature
Project description:Thanks to the advanced technologies for energy generation such as solar cells and thermo- or piezo-generators the amount of electricity transformed from light, heat or mechanical pressure sources can be significantly enhanced. However, there is still a demand for effective storage devices to conserve electrical energy which addresses the wide range of large stationary applications from electric vehicles to small portable devices. Among the large variety of energy-storage systems available today, electrochemical energy sources and, in particular, supercapacitors (SC), are rather promising in terms of cost, scaling, power management, life cycle and safety. Therefore, this review surveys recent achievements in the development of SC based on composites of such carbon-derived materials as graphene (G) and reduced graphene oxide (rGO) with carbon nanotubes (CNT). Various factors influencing the specific capacitance are discussed, while specific energy and power as well as cycling stability of SC with G/rGO-CNT composite electrode materials are overviewed.
| S-EPMC8151991 | biostudies-literature
Project description:The literature on polar Gallium Nitride (GaN) surfaces, surface treatments and gate dielectrics relevant to metal oxide semiconductor devices is reviewed. The significance of the GaN growth technique and growth parameters on the properties of GaN epilayers, the ability to modify GaN surface properties using in situ and ex situ processes and progress on the understanding and performance of GaN metal oxide semiconductor (MOS) devices are presented and discussed. Although a reasonably consistent picture is emerging from focused studies on issues covered in each of these topics, future research can achieve a better understanding of the critical oxide-semiconductor interface by probing the connections between these topics. The challenges in analyzing defect concentrations and energies in GaN MOS gate stacks are discussed. Promising gate dielectric deposition techniques such as atomic layer deposition, which is already accepted by the semiconductor industry for silicon CMOS device fabrication, coupled with more advanced physical and electrical characterization methods will likely accelerate the pace of learning required to develop future GaN-based MOS technology.
| S-EPMC5448900 | biostudies-literature
Project description:Degenerately doped ZnO is seen as a potential substitute to the ubiquitous and expensive Sn doped In2O3 as a transparent electrode in optoelectronic devices. Here, highly conductive and transparent Ga doped ZnO thin films were grown via aerosol assisted chemical vapor deposition. The lowest resistivity (7.8 × 10-4 Ω.cm) and highest carrier concentration (4.23 × 1020 cm-3) ever reported for AACVD grown ZnO: Ga was achieved due to using oxygen poor growth conditions enabled by diethylzinc and triethylgallium precursors.
| S-EPMC6971236 | biostudies-literature