A single ion conducting separator and dual mediator-based electrolyte for high-performance lithium–oxygen batteries with non-carbon cathodes

2018 ◽  
Vol 6 (21) ◽  
pp. 9816-9822 ◽  
Author(s):  
Shichao Wu ◽  
Yu Qiao ◽  
Han Deng ◽  
Haoshen Zhou
Keyword(s):  
High Performance ◽  
Carbon Cathode ◽  
Improved Performance ◽  
Ion Conducting ◽  
Lithium Oxygen Batteries

Lithium–oxygen batteries with non-carbon cathode realize largely-improved performance by designing mediators and Li+-Nafion separator to prevent self-discharge and shuttle problems.

scholarly journals Polymer/Iron-Based Layered Double Hydroxides as Multifunctional Wound Dressings

Pharmaceutics ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 1130
Author(s):  
Mariana Pires Figueiredo ◽  
Ana Borrego-Sánchez ◽  
Fátima García-Villén ◽  
Dalila Miele ◽  
Silvia Rossi ◽  
...  
Keyword(s):  
Drug Release ◽  
High Performance ◽  
Mechanical Performance ◽  
Release Kinetics ◽  
Wound Dressings ◽  
In Vitro Drug Release ◽  
Improved Performance ◽  
Double Hydroxide ◽  
Double Hydroxides

This work presents the development of multifunctional therapeutic membranes based on a high-performance block copolymer scaffold formed by polyether (PE) and polyamide (PA) units (known as PEBA) and layered double hydroxide (LDH) biomaterials, with the aim to study their uses as wound dressings. Two LDH layer compositions were employed containing Mg2+ or Zn2+, Fe3+ and Al3+ cations, intercalated with chloride anions, abbreviated as Mg-Cl or Zn-Cl, or intercalated with naproxenate (NAP) anions, abbreviated as Mg-NAP or Zn-NAP. Membranes were structurally and physically characterized, and the in vitro drug release kinetics and cytotoxicity assessed. PEBA-loading NaNAP salt particles were also prepared for comparison. Intercalated NAP anions improved LDH–polymer interaction, resulting in membranes with greater mechanical performance compared to the polymer only or to the membranes containing the Cl-LDHs. Drug release (in saline solution) was sustained for at least 8 h for all samples and release kinetics could be modulated: a slower, an intermediate and a faster NAP release were observed from membranes containing Zn-NAP, NaNAP and Mg-NAP particles, respectively. In general, cell viability was higher in the presence of Mg-LDH and the membranes presented improved performance in comparison with the powdered samples. PEBA containing Mg-NAP sample stood out among all membranes in all the evaluated aspects, thus being considered a great candidate for application as multifunctional therapeutic dressings.

scholarly journals SnS2/TiO2 Nanocomposites for Hydrogen Production and Photodegradation Under Extended Solar Irradiation

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 589
Author(s):  
Sivagowri Shanmugaratnam ◽  
Balaranjan Selvaratnam ◽  
Aravind Baride ◽  
Ranjit Koodali ◽  
Punniamoorthy Ravirajan ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Hydrogen Evolution ◽  
Environmental Remediation ◽  
High Performance ◽  
Degradation Mechanism ◽  
Solar Irradiation ◽  
Earth Abundant ◽  
Improved Performance ◽  
Chalcogenide Materials

Earth–abundant transition metal chalcogenide materials are of great research interest for energy production and environmental remediation, as they exhibit better photocatalytic activity due to their suitable electronic and optical properties. This study focuses on the photocatalytic activity of flower-like SnS2 nanoparticles (composed of nanosheet subunits) embedded in TiO2 synthesized by a facile hydrothermal method. The materials were characterized using different techniques, and their photocatalytic activity was assessed for hydrogen evolution reaction and the degradation of methylene blue. Among the catalysts studied, 10 wt. % of SnS2 loaded TiO2 nanocomposite shows an optimum hydrogen evolution rate of 195.55 µmolg−1, whereas 15 wt. % loading of SnS2 on TiO2 exhibits better performance against the degradation of methylene blue (MB) with the rate constant of 4.415 × 10−4 s−1 under solar simulated irradiation. The improved performance of these materials can be attributed to the effective photo-induced charge transfer and reduced recombination, which make these nanocomposite materials promising candidates for the development of high-performance next-generation photocatalyst materials. Further, scavenging experiments were carried out to confirm the reactive oxygen species (ROS) involved in the photocatalytic degradation. It can be observed that there was a 78% reduction in the rate of degradation when IPA was used as the scavenger, whereas around 95% reduction was attained while N2 was used as the scavenger. Notably, very low degradation (<5%) was attained when the dye alone was directly under solar irradiation. These results further validate that the •OH radical and the superoxide radicals can be acknowledged for the degradation mechanism of MB, and the enhancement of degradation efficiency may be due to the combined effect of in situ dye sensitization during the catalysis and the impregnation of low bandgap materials on TiO2.

Improved performance of SrFe12O19 bulk magnets through bottom-up nanostructuring

Nanoscale ◽  
2016 ◽  
Vol 8 (5) ◽  
pp. 2857-2866 ◽  
Author(s):  
Matilde Saura-Múzquiz ◽  
Cecilia Granados-Miralles ◽  
Marian Stingaciu ◽  
Espen Drath Bøjesen ◽  
Qiang Li ◽  
...  
Keyword(s):  
Spark Plasma Sintering ◽  
High Performance ◽  
Single Domain ◽  
Bottom Up ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Improved Performance ◽  
Supercritical Synthesis

High-performance hexaferrite magnets of aligned single-domain nanoplatelets are obtained by supercritical synthesis and compaction through Spark Plasma Sintering.

scholarly journals Recent Progress on Catalysts for the Positive Electrode of Aprotic Lithium-Oxygen Batteries †

Inorganics ◽  
2019 ◽  
Vol 7 (6) ◽  
pp. 69 ◽  
Author(s):  
Yichao Cai ◽  
Yunpeng Hou ◽  
Yong Lu ◽  
Jun Chen
Keyword(s):  
High Performance ◽  
Noble Metals ◽  
Catalytic Mechanism ◽  
Low Cost ◽  
Rate Capability ◽  
Positive Electrode ◽  
Safety Hazards ◽  
Environmental Friendliness ◽  
Potential Safety ◽  
Lithium Oxygen Batteries

Rechargeable aprotic lithium-oxygen (Li-O2) batteries have attracted significant interest in recent years owing to their ultrahigh theoretical capacity, low cost, and environmental friendliness. However, the further development of Li-O2 batteries is hindered by some ineluctable issues, such as severe parasitic reactions, low energy efficiency, poor rate capability, short cycling life and potential safety hazards, which mainly stem from the high charging overpotential in the positive electrode side. Thus, it is of great significance to develop high-performance catalysts for the positive electrode in order to address these issues and to boost the commercialization of Li-O2 batteries. In this review, three main categories of catalyst for the positive electrode of Li-O2 batteries, including carbon materials, noble metals and their oxides, and transition metals and their oxides, are systematically summarized and discussed. We not only focus on the electrochemical performance of batteries, but also pay more attention to understanding the catalytic mechanism of these catalysts for the positive electrode. In closing, opportunities for the design of better catalysts for the positive electrode of high-performance Li-O2 batteries are discussed.

scholarly journals Development of improved performance electromagnetic valve for liquid rocket engine

2020 ◽  
Vol 19 (4) ◽  
pp. 30-42
Author(s):  
A. A. Igolkin ◽  
T. A. Chubenko ◽  
A. D. Maksimov
Keyword(s):  
Magnetic Induction ◽  
High Performance ◽  
Rocket Engine ◽  
Mathematic Model ◽  
Liquid Rocket Engine ◽  
Electromagnetic Valve ◽  
Magnetic Induction Distribution ◽  
Improved Performance ◽  
Liquid Rocket ◽  
Distribution Field

The problem of developing optimal-design electromagnetic valves is relevant for many industries. The development of technology is characterized by increased power and pressures used for actuator mechanisms, as well as by reducing the dimensions and mass of automatic units. The goal of this article is to develop an advanced electromagnetic valve that would ensure optimal combination of high performance, reliability, technological effectiveness and minimal cost. On the basis of standard dependences for electromagnetic phenomena a mathematic model of a SU.1 valve was developed. It was calculated in several special-purpose software packages: NISA, FEMM, ANSYS Maxwell. Parametric analysis was implemented in ANSYS Maxwell for variable working gap settings and values of current force in the solenoid. As a result, the magnetic induction distribution field was obtained. The results of modeling the operation of the electromagnetic valve and the magnetic induction distribution field are presented for variable working gap settings and different values of current force in the solenoid. The model of an advanced electromagnetic valve for a liquid rocket engine was developed on the basis of the dependences obtained. The duration of single engine firing obtained is 40 msec. The results obtained make it possible to create a valve with hold-open time of 800msec, which is considered sufficient for application in electromagnetic direct current valves.

scholarly journals Fabrication of Strontium Bismuth Oxides as Novel Battery-Type Electrode Materials for High-Performance Supercapacitors

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Yinghui Han ◽  
Le Li ◽  
Yunpeng Liu ◽  
Xue Li ◽  
Xiaohan Qi ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
High Performance ◽  
Electrode Materials ◽  
Specific Capacity ◽  
Structural Features ◽  
High Electron ◽  
Strontium Content ◽  
X Ray ◽  
Bismuth Oxides ◽  
Improved Performance

A simple and efficient process method for the preparation of strontium bismuth oxides (SBOs) via an impregnation-calcination method is presented. The synthesized active materials are characterized using X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. The electrochemical performance of the as-synthesized SBO samples is observed to decrease gradually as the strontium content is increased from 25% to 50%. The SBO sample with a Sr/Bi ratio of 1 : 3 shows the highest specific capacitance of 1228.7 F g−1 (specific capacity of 204.8 mAh g−1) at a current density of 1 A g−1 and a good cycling stability (75.1%) over 3000 charge-discharge cycles. The improved performance of the supercapacitors can be attributed to the unique structural features resulting from the addition of appropriate portions of Sr, which supports high electron conductivity and rapid ion/electron transport within the electrode and at the electrode/electrolyte interface. All the results show that the SBOs have considerable potential for use as high-performance battery-type electrodes in supercapacitors.

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