Cathode Research Articles

Nanosheets Self-Assembled 3D LiFeO4/Graphene as Cathode Material for Lithium-Ion Batteries

In order to understand the feasibility of using graphene as cathode materials for lithium-ion batteries, this paper uses graphene as an additive to prepare graphene-coated three-dimensional flower-shaped FeO4 nanostructures by one-step hydrothermal method. The obtained composite nano-material is composed of FeO4 nano flower-balls assembled by graphene and dozens of nanosheets. The crystal structure and morphology of the material were characterized by XRD and SEM, and their electrochemical properties were also studied. After cycling 50 times at a current density of 1000 m Ah/g, the reversible capacity of the FeO4/graphene composite still reaches 503.1 m Ah/g and the capacity retention rate is as high as 82%.

Null effects of tDCS over the Left Prefrontal Cortex on Self-paced Exercise and EEG

Purpose : to test the hypothesis that transcranial direct current stimulation (tDCS) over the left dorsolateral prefrontal cortex (DLPFC) influences performance in a 20’ self-paced exercise and electroencephalographic (EEG) oscillatory brain activity in a group of trained male cyclists. Methods : We conducted a pre-registered (https://osf.io/rf95j/), randomised, sham-controlled, within-subject design experiment. 36 trained males cyclists, age 27 (6.8) years, VO2max: 54 (6.13) ml/min/kg, completed a 20’ self-paced exercise in three separate sessions, under three stimulation conditions: anodal, cathodal and sham. TDCS was delivered for 20' before each test at a current intensity of 2.0 mA. The anode electrode was placed over the DLPFC and the cathode over the shoulder. We measured the power output, heart rate, RPE and EGG (at baseline and during exercise). Results : The were not difference in power output (F = 0.031 = 0.31, p > 0.05) during the self-paced exercise between conditions: Anodal (235 W [95%CI 222 - 249 W]; Cathodal (235 W [95%CI 222 - 248 W] and Sham (234 W [95%CI 220 - 248 W]. Neither the heart rate, RPE nor EEG activity were affected by the tDCS (all Ps > 0.05). Conclusions : tDCS over the left DLFC did not affect self-paced exercise performance in trained cyclists. Moreover, tDCS did not elicit any change on EEG activity either at baseline or during exercise. Our data suggest that the significant effects of tDCS on endurance performance (and at rest) reported by recent studies should be taken with caution. Acknowledgments This project was supported by grants from from the Spanish Ministerio de EconomA­a, Industria y Competitividad-PSI2016-75956-P- to Daniel Sanabria and Mikel Zabala, a predoc-toral grant from the Spanish Ministerio de EconomA­a, Industria y Competitividad (BES-2014-069050) to Luis Ciria, and a Spanish “Ministerio de EducaciA³n, Cultura y Deporte” predoctoral grant (FPU14/06229) to DarA­as Holgado.

Designing and Developing Rechargeable Aluminium-Ion Battery using Graphite Coated Activated Charcoal Corncob as Cathode Material

One of the renewable energy storage systems that can be used today is the aluminum ion battery. In this study, aluminum foil was used as anode, polyetylene polyprophylene (PE/PP) as separator, electrolyte from AlCl3/[EMIm]Cl and graphite coated corncob, an activated charcoal, as cathode. Coating method of cathode materials was done by mixing both graphite and activated charcoal with varied composition 1:0.5, 1:1, 1:1.5, and 1:3. The coating process began by mixing the graphite and corncob with ethanol as a solvent for six hours, then heating in an oven at 80 °C for three days, gradual drying in a furnace at 350 °C for five hours and sintering at 600 °C for six hours. From this research, SEM results showed that carbon particles were evenly distributed, with spherical particles. The spherical shape was the main requirement of carbon formation in order to produce high energy. Based on the results, battery potential was 2.54 V with average of optimal capacity at a ratio of graphite and corncob activated charcoal 1:1.5 was 83.067 mAh/g. The highest efficiency was also at a ratio of 1:1.5 of 97.20%, because at this ratio, there was an increasing in percentage of element C 91.74%, greater than the percentage of element C on the other three cathode samples.Salah satu sistem penyimpan energi terbarukan yang bisa digunakan saat ini adalah baterai ion aluminium. Pada penelitian ini digunakan aluminium foil sebagai anoda, polyetylene polyprophylene (PE/PP) sebagai separator, elektrolit menggunakan AlCl3/[EMIm]Cl dan grafit terlapisi arang aktif tongkol jagung sebagai bahan katoda. Metode pelapisan bahan katoda dilakukan dengan mencampurkan grafit dan arang aktif dengan variasi komposisi 1:0,5, 1:1,1:1,5 dan 1:3. Proses pelapisan diawali dengan pencampuran grafit dan arang aktif tongkol jagung dengan ethanol sebagai pelarut selama enam jam kemudian pemanasan di oven pada suhu 80oC selama tiga hari, pengeringan bertahap di furnace pada suhu 350oC selama lima jam dan sintering pada suhu 600oC selama enam jam. Dari penelitian ini didapatkan hasil SEM menunjukkan bahwa partikel karbon terdistribusi merata, dengan bentuk partikel bulat (sphare).Sampelberbentuk bulat atau sphere merupakan syarat utama pembentukan karbon supaya dapat menghasilkan energi tinggi. Berdasarkan hasil uji baterai diperoleh potensial sebesar 2,54 Volt dengan rata-rata kapasitas optimal terjadi pada rasio grafit dan arang aktif tongkol jagung 1:1,5 sebesar 83,067 mAh/g. Efisiensi tertinggi juga terjadi pada rasio 1:1,5 sebesar 97,20%. Hal ini karena pada rasio 1:1,5 terjadi peningkatan persentase unsur C yakni 91.74% lebih besar dari persentase unsur C pada tiga sampel katoda yang lainnya.

Spinel Lithium Manganese Oxide Octahedral Nanoparticles with Excellent Electrochemical Performance as Cathode Materials for Lithium-Ion Batteries

Spinel Lithium Manganese Oxide Octahedral Nanoparticles with Excellent Electrochemical Performance as Cathode Materials for Lithium-Ion Batteries

Recent Progress in the Lithium-Rich Ternary Layered Cathode Materials

Recent Progress in the Lithium-Rich Ternary Layered Cathode Materials

Efficiency of remobilisation of chromium precipitates in an aquifer permeable reactive barrier

Chromium exists largely in two oxidation states, namely Cr(VI) which is carcinogenic and mutagenic to living organisms including humans, and Cr(III) which is about 1,000 times less toxic than Cr(VI). It is therefore desirable in most cases to reduce Cr(VI) to Cr(III) as the first step towards complete treatment of Cr(VI). Various studies have been conducted on the Cr(VI) reduction process either in situ or ex situ. However, in situ bioremediation using permeable reactive barrier systems offers an attractive option compared to other in situ technologies. This study was conducted to evaluate the reduction of Cr(VI) to Cr(III) in the short term and regeneration of the biological reactive barrier to achieve continuous long-term operation. It was observed from the study that the chromium hydroxide Cr(OH)3(s) precipitated and thus affected the porosity and hydraulic conductivity of the barrier system. The precipitate could be washed using a dilute acid solution. However, lowering the pH in the reactor introduced harsh conditions which necessitated the evaluation of a possible culture shift during the regeneration phase. Microbial culture composition during bioremediation and after soil washing with dilute acid was evaluated using the 16S rRNA genotype fingerprinting. The microbial barrier was initially inoculated with indigenous bacterial species from dried sludge. The results showed the presence of well-known Cr(VI) reducers such as Bacillus mycoides, Lysinibacillus fusiformis and Micrococcus lylae in the microbial community of the barrier. The microbial barrier system successfully achieved near complete removal of Cr(VI), whereby approximately 75 % Cr(VI) removal was achieved within 63 days of operation. The formation of Cr(OH)3(s) was observed in the second week of operation. After 4 weeks of operating the microcosm under soil washing with 0.1 % HCl and electrokinetics remediation with a DC voltage of 50-150 V, an increase in total chromium (73 %) was observed suggesting that the trapped chromium species in the microcosm was effectively remobilized with the assumption that Cr(III) had attached to the cathode forming a white-yellow precipitate layer around the cathode. Additionally, more than 95 % Cr(VI) was transformed during electrokinetic and soil washing remediation. However, one of the limitations of electrokinetic remediation is the near anode focusing effect whereby a layer of precipitate is formed around the anode that leads to the reduction in mobility of the species through the aquifer medium.

Degradation Mechanism of Nickel-Cobalt-Aluminum (NCA) Cathode Material from Spent Lithium-Ion Batteries in Microwave-Assisted Pyrolysis

Degradation Mechanism of Nickel-Cobalt-Aluminum (NCA) Cathode Material from Spent Lithium-Ion Batteries in Microwave-Assisted Pyrolysis

Model of cardiac arrest in rats established by modified transcutaneous electrical stimulation on epicardium

Objective To establish the cardiac arrest (CA) model in rats by modified transcutaneous electrical stimulation on epicardium. Methods This study was performed in the Emergency Medicine laboratory in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology. After 10 Sprague-Dawley male rats weighing 330-380 g were anesthetized, two acupuncture needles connected to the anode and cathode of a stimulator were transcutaneously inserted into the epicardium as electrodes. The puncture points were located quantitatively according to the anatomical structure of the rat chest. The electrical stimulation was maintained for 3 minutes to induce ventricular fibrillation(VF). Cardiopulmonary resuscitation (CPR) included chest compressions, intravenous adrenaline and defibrillation operated at 6 min after a period of nonintervention. Results CA was induced after the implement of the effective electrical stimulation in all ten rats in this experiment. The average current intensity to induce VF was (1.80 ± 0.59) mA, the average time to induce CA was (5.07 ± 2.37) s, the average time of the total electrical stimulation was (187.50 ± 12.75) s and the total time of CA was 6 min. At the end of the electrical stimulation, 9 rats presented VF and 1 rat showed pulseless electrical activity. The restoration of spontaneous circulation was achieved in all 10 rats. The average time of CPR was(190.90±68.60) s, the mean numbers of defibrillation were(1.20 ± 0.63) , and he average number of adrenaline application were (1.20 ± 0.42) times. Neither visible hemorrhage on epicardium nor gross pulmonary congestion was observed. Conclusions The modified transcutaneous electrical stimulation on epicardium to produce CA model in rats is an easily applicable and effective technique. This model may provide an alternative for experimental research of CPR. Key words: Ventricular fibrillation; Cardiac arrest; Modified method; Electrical epicardium stimulation; Rat

Effect of ph at anode and cathode chamber on the performance of biological cathodic protection

A new corrosion control system which is biological cathodic protection (CP) system was developed using the concept of microbial fuel cells (MFCs). Microorganisms available in domestic wastewater was utilised to generate electrons and supplied to the carbon steel pipe, and as consequence, protect the pipe from corrosion. There are various factors affect the performance of the system including the pH at the anode and cathode chamber. This study aims to analyse the optimum pH at anode and cathode. In this study, wastewater was used as the electrolyte and graphite rod as the electrode in the anode compartment while cathode compartment was filled with sand and carbon steel pipe acts as the cathode. Both compartments were connected by a plastic tubing and separated by the membrane. It was found that optimum pH at anolyte and catholyte were 8 and 6. The CP potential versus copper sulfate electrode (CSE) was -752 mV. It shows that the corrosion of carbon steel pipe was reduced since the native potential of the carbon steel pipe versus CSE was -560 mV.

The effect of potential to colour and cod removal from waste textile industry by electrochemical method

The waste textile industry is one of the problems to the human life as well as environment. In this study, the treatment of the waste textile industry by the electrochemical method using stainless steel as anode and cathode was investigated. The effect of potential to color and COD removal were investigated. The research consists of several stages, the electrode composition analysis using Scanning Electron Microscopy-Energy Dispersive X-Ray (SEM-EDX). The electrolysis waste textile industry has been done using various potential. Degradation parameter is Chemical Oxygen Demand (COD) were analysis using spectrometry method. The research results show that stainless steel electrode has composition are iron (72.2 %), chromium (18.9 %), nickel (7.6 %) and silica (1.4 %). After electrolysis at potential constant (3 V) shows percentage degradation of the waste textile industry is 98.56 %. The percentage reduction in COD value of textile waste electrolyzed in optimum condition is 50.38 %. As conclusions are the potential at 3 V and stainless-steel electrode as a good parameter and material for electrochemical degradation of the waste textile industry.

Umicore raises $1.1 bn to invest in cathode business.

Umicore raises $1.1 bn to invest in cathode business.

Umicore directs $1.1 billion at cathodes

Umicore directs $1.1 billion at cathodes

Umicore directs $1.1 billion at cathodes

Umicore directs $1.1 billion at cathodes

MoS2‐Nanosheet‐Decorated Carbon Nanofiber Composites Enable High‐Performance Cathode Materials for Mg Batteries

AbstractIn rechargeable Mg batteries, kinetically reasonable and electrolyte‐compatible cathode materials are required to achieve high electrochemical performance. Here, we report a high‐performance rechargeable Mg battery cathode material that is constructed from layered structural MoS2 nanosheets decorated on conductive nitrogen‐doped carbon nanofibers (N‐CNFs@MoS2). We demonstrate that N‐CNFs@MoS2 exhibits good electrochemical compatibility in two types of dual‐salt electrolytes including an all‐phenyl complex with lithium chloride (LiCl‐APC) and bis(trifluoromethane)sulfonimide lithium salt with magnesium chloride (MgCl2‐LiTFSI). The fabricated N‐CNFs@MoS2‐Mg batteries based on both dual‐salt electrolyte systems exhibit good cyclic stability and high rate performance.

Evaluation of La0.6Sr0.4Co0.2Fe0.8O3-δ as a potential cathode for proton-conducting solid oxide fuel cell

The application of La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) as a potential cathode working on a BaCe0.54Zr0.36Y0.1O2.95 (BCZY) electrolyte for proton conducting solid oxide fuel cell was investigated. LSCF nanoceramic powders were synthesized by an activated carbon-assisted sol-gel process using metal nitrate-based chemicals. The LSCF powder was transformed to a slurry and spin-coated onto both surfaces of BCZY pellet to form a symmetrical cell with the configuration of LSCF|BCZY|LSCF. The symmetrical cell was subsequently sintered at 950°C for 2 h to allow a good contact formation between electrode/ electrolyte layers. The phase structural verification of the calcined powders was investigated by X-Ray diffractometer (XRD). Field-emission scanning electron microscopy (FESEM) was employed to examine the morphology of the sintered cell. The electrochemical behaviour of the symmetrical cell was studied by an electrochemical impedance spectroscopy. The formation of a single perovskite LSCF phase with a crystallite size of 20 nm was obtained at 700°C as corroborated by XRD analysis. The FESEM images showed a good contact between LSCF cathode and BCZY electrolyte at electrode/ electrolyte interfacial layer. The ASR obtained for LSCF symmetrical cell measured at 700°C with and without Pt current collector is 0.87 and 31.25 Ωcm2, respectively.

Verification of a cathode pressure drop model for single phase flow in a proton exchange membrane fuel cell

Verification of a cathode pressure drop model for single phase flow in a proton exchange membrane fuel cell

Effect of Humidifier Temperatures on Nafion-XL Membrane Electrode Assemblies (MEA) – An Experimental Study

The importance of fuel cell as energy source is known ubiquitously. In this regard, studies were carried out on fuel cell test station employing a new membrane, Nafion-XL by Dupont. Data were obtained on cell voltage, power, efficiency, transient response etc. Two systems have been considered in the present case viz., hydrogen/air and hydrogen/oxygen. Naturally hydrogen/oxygen system proved to be superior than hydrogen/air in terms of performance. Optimum anode and cathode humidification temperatures were obtained experimentally for both the systems. Optimum fuel cell operation temperature is found to be 65°C. Anode humidification temperature is the key parameter that exhibited considerable influence on fuel cell performance in the present studies.

Effect of Cathodes Prepared with Different Compositions on the Performace of Li-Sulfur Secondary Battery

다양한 전자제품에서 높은 성능의 이차 전지가 요구됨에 따라 안전하고 친환경적이며 경제적인 이차 전지 전극 재료의 개발을 필요로 하고 있다. 리튬-황 배터리는 높은 이론용량과 에너지밀도, 그리고 친환경적인 물질이라는 점에서 차세대 이차전지로써 주목받고 있지만, 폴리설파이드의 용출로 인한 전지 용량감소현상이...

Numerical Analysis in Mesoscopic Scale and Experimental Verification for Sodium Expansion Induced Stress of Cathode Carbon Blocks

Numerical Analysis in Mesoscopic Scale and Experimental Verification for Sodium Expansion Induced Stress of Cathode Carbon Blocks

Tibial nerve stimulation to inhibit the micturition reflex by an implantable wireless drivermicrostimulator in cats

Objective Objective To evaluate the effects of a new type of tibial nerve micro-stimulator on the micturition reflex in cats. Methods From March to May in 2017, the implantable wireless driver micro-stimulator was implanted around the tibial nerve in 9 α-chloralose anesthetized domestic shorthairs cats (2.5-3.5 kg, 6-12 months old). The stimulator was placed near the neurovascular bundle parallel to the tibial nerve and its cathode perpendicular to the cushion. The intensity which can induce toe movement was defined as threshold(T). The ureters were isolated via an abdominal incision. The ureters were cut and drained externally. The bladder was inserted via a double lumen catheter through the urethra. The catheter was then secured by a ligature around the urethra. One lumen of the catheter was used to infuse the bladder with either 0.9% normal saline (NS) or 0.25% AA at a rate of 1 to 2 ml/min after connecting to a pump. The other lumen was connected to a pressure transducer to measure the bladder pressure. The bladder capacity was used to test the inhibitory effect of the stimulator. After the appearance of the first large-amplitude (>30 cmH2O) bladder contraction, the bladder infusion was stopped.First, after emptying the bladder, 2 or 3 cystometrograms with NS were performed without stimulation to obtain the control bladder capacity. After the bladder was stabilized, TNS (6 Hz, 1-2 T) was applied during 2 sequential cystometrograms. Second, after emptying the bladder, 0.25% AA was infused into the bladder to irritate and induce bladder overactivity. After the bladder stabilized, TNS (6 Hz, 1-2 T) was applied again during 2-3 sequential cystometrograms.If bladder capacity increased significantly, the stimulationhad an inhibitory effect on the micturition reflex. Results During normal saline infusion, the bladder baseline was (17.03±4.10)ml. TNS at 1T did not change the bladder capacity [(18.56±0.81)ml](P>0.05). TNS at 2T significantly increased the bladder capacity [(25.05±1.19)ml](P 0.05). TNS at 2T significantly increased the bladder capacity [(14.82±1.15)ml](P<0.05). Conclusions The implantable wireless driver tibial nerve micro-stimulator appears to be effective in inhibiting the micturition reflex during physiologic and pathologic conditions. The implantable wireless driver tibial nerve micro-stimulator was excepted to be used to treat overactive bladder (OAB). Key words: Cat; Implantable; Microstimulator; Micturition reflex; Tibial nerve stimulation