batterydata/paper-abstracts huggingface dataset:
Mo-doped Li3Mo x V2−x (PO4)3/C (x =0, 0.01, 0.02, 0.03 and 0.04) are prepared through a fast sol–gel method. The X-ray diffractometer, scanning electron microscopy and high-resolution transmission electron microscopy are employed to characterize the prepared materials, and the evidences show that Mo element have been successfully incorporated into the Li3V2(PO4)3 lattice. The Li3Mo0.03V1.97(PO4)3/C composite exhibits the most excellent electrochemical performance among all the samples. In the potential range of 3.0–4.3V, Li3Mo0.03V1.97(PO4)3/C exhibits the discharge capacities of 125.0mAhg−1 and 122.8mAhg−1 at 5C and 10C rates, respectively. A capacity of 117.6mAhg−1 is still delivered at 20C rate after 150 cycles with a capacity retention of 93.6%. In addition, the electrochemical impedance spectroscopy test proves that the electronic conductivity of Li3Mo0.03V1.97(PO4)3/C is decreased, while the lithium ion conductivity is increased compared with the un-doped one. Based on above results, we conclude that the solid state diffusion of lithium ions is the rate-determining step of the extraction/insertion process.
Savant syndrome is a condition where prodigious talent can co-occur with developmental conditions such as autism spectrum conditions (autism). It is not yet clear why some autistic people develop savant skills while others do not.
Carbon nanotubes (CNT) fabrics were studied and evaluated as anode current collectors, replacing the traditional copper foil current collector in Li-ion batteries. Glavanostatic measurements reveal high values of irreversible capacities (as high as 28%), resulted mainly from the formation of the solid electrolyte interphase (SEI) layer at the CNT fabric surface. Various pre-treatments to the CNT fabric prior to active anode material loading have shown that the lowest irreversible capacity is achieved by immersing and washing the CNT fabric with iso-propanol (IPA), which dramatically modified the fabric surface. Additionally, the use of very thin CNT fabrics (5 μm) results in a substantial irreversible capacity minimization. A combination of IPA rinse action and utilization of the thinnest CNT fabric provides the lowest irreversible capacity of 13%. The paper describes innovative and rather simple techniques towards a complete implementation of CNT fabric as an anode current collector in Li-ion batteries, instead of the relatively heavy and expensive copper foil, enabling an improvement in the gravimetric and volumetric energy densities of such advanced batteries.
The structural behaviour of the sol–gel chromium–vanadium mixed oxide Cr0.11V2O5.16 is investigated as electrochemical lithium insertion proceeds. Electrochemically reduced electrodes are examined by XRD over the large Li composition range 0< x ≤2 in Li x Cr0.11V2O5.16. New fingerprints of lithiated phases are obtained in comparison with available data in the Li–V2O5 system. It is shown that lithiation produces an ɛ-related phase over a wide composition range 0.18≤ x ≤2 whose interlayer distance linearly increases with x which strongly contrasts with the successive appearance of the (α/ɛ), (ɛ/δ), and (δ/γ) wide biphasic regions for the Li x V2O5 system. The existence of shorts chains of CrO6 octahedra perpendicular to V2O5 layers increases the three-dimensional character of the host lattice impeding then too strong deformations to occur. These limited structural changes resulting in a single phase behaviour are discussed in relation with the original and promising electrochemical properties of the sol–gel mixed oxide Cr0.11V2O5.16.
We have reported fast and simple synthesis of electrochemically reduced graphene oxide nanosheets (ErGO NSs)-embedded-palladium nanoparticles (Pd-E-ErGO) hybrids on nickel (Ni) sheet for high performance electrochemical supercapacitors (SCs) electrode. The Pd-E-ErGO hybrids material was successfully prepared by facile and one-pot in-situ electrochemical reduction and deposition using water as solvent in which palladium nanoparticles (Pd NPs) were uniformly embedded inside 2D-nanosheets of ErGO. During electrochemical reduction, graphene oxide nanosheets were reduced into ErGO NSs and PdCl2 ionized to form Pd2+ which attracted to the negative oxygen containing functional groups of ErGO NSs then reduced to form Pd NPs which embedded completely between ErGO NSs structure. The surface/structural morphology of Pd-E-ErGO hybrids was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), energy-dispersive X-ray spectroscopy (EDS) and Raman spectroscopy. The proportions of elements present in hybrids were determined by EDS and thermogravimetric analysis (TGA). As an application, the synthesized Pd-E-ErGO hybrids revealed enhanced electrochemical performance as high specific capacitance with excellent cycling stability which was very significant for electrochemical SCs. The Pd-E-ErGO hybrids electrode fulfills an approving specific capacitance value of 1524.7 F/g at a scan rate of 20 mV/s and improved cycling stability of 92.1% capacitance retention after 2000 cycles in the three-electrode setup. The electrochemical synthesis of Pd-embedded-graphene derivatives structure as well as improved electrochemical performance for SCs opens up a new idea to prepare electrode materials.
Directed methanol fuel cells (DMFCs) are fabricated on printed circuit board (PCB) substrates by means of a photolithography process. The effects of channel pattern, channel width and methanol flow rate on the performance of the fabricated DMFC are evaluated over a range of flow-channel widths from 200 to 400μm and flow rates of methanol from 2 to 80mlmin−1. A micro-DMFC with a cross-stripe channel pattern gives superior performance compared with zig-zag and serpentine type of pattern. A single cell with a 200-μm wide channel delivers a maximum power density of 33mWcm−2 when using 2M methanol feed at 80°C. An air-breathing multi-DMFC composed of eight single unit cells gave 180mWcm−2 by using a methanol reservoir. It is considered that this may be the first reported attempt to develop a multi-DMFC with micro-channels fabricated on a PCB substrate.
In this work, we develop a bifunctional composite comprised of hierarchical flower-like NiMn-layered double hydroxides (LDH) nanoarrays grown on melamine sponge-derived carbon (SC). This composite material is used as a flexible asymmetric supercapacitor positive electrode and oxygen evaluation reaction (OER) electrocatalyst. Integrated carbon foams with controllable three-dimensional pores are easily obtained and served as conductive backbones for the growth of the flower-like NiMn-LDH nanoarrays. The as-prepared flexible electrode, combining a highly open scaffold-like structure with well-designed electron transfer channels, shows significantly enhanced cyclic stability (99.6% of the initial activity maintained after 5000 cycles) and high energy density (41.0 Wh·Kg−1) in aqueous electrolyte. The as-prepared SC@NiMn-LDH@G//NPC asymmetric supercapacitor can lighten a LED indicator for more than 10minutes. Additionally, this composite presents extremely low overpotentials (220mV at 10 mA·cm−2) and low Tafel slopes (30 mV·dec−1) in alkaline medium. This OER performance is one of the best reported so far among the state of art electrocatalysts.
The paper discusses the synthesis, photoelectrochemical and electrochemical behaviour of titania nanotube arrays modified by a pyrolyzed metal-organic framework (MOF). A poly(3,4–ethylenedioxyphene) (PEDOT) matrix with an embedded inorganic network of iron hexacyanoferrate (BP) covering TiO2 nanotubes (TNT) is used as a MOF for the further sintering procedure, resulting in a novel, thin film of carbonaceous wrap supported Fe catalytic centers: TNT@C:Fe. UV–Vis and Raman spectroscopies were utilized to characterize the absorbance capability and the crystalline phase of titania, respectively. XPS was used for identification of the valence stage of iron Fe(0), Fe(II), Fe(III) in the shell part of the novel composite TNT@C:Fe. The electrochemical performance of the modified nanotubular TiO2 electrodes has been monitored by cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge/discharge cycles in an aqueous electrolyte. TNT@C:Fe exhibited the capacitance of 9.1 mF cm−2 even after 5000 cycles, being much higher than pure titania (2.1 mF cm−2). The photocurrent density reached 304 μA cm−2 for TNT@C:Fe, whereas only 32 μAcm−2 was registered for pure titania nanotubes under simulated solar light illumination at a potential of +0.5 V. An improved decolorization rate of methylene blue in water confirms enhanced photoactivity of TNT@C:Fe in comparison with pristine titania nanotubes.
Tailored high-activity cathode materials are of great importance for construction of high-performance capacitors and hybrid batteries. In this work, we report a facile template-free chemical bath deposition method to fabricate porous Co3O4 nanoflake microspheres consisting of self-assembled nanoflakes with thicknesses of ∼10nm. The as-prepared Co3O4 microspheres have average diameters of ∼2μm and the secondary Co3O4 nanoflakes are interconnected with each other forming a highly open net-structure with pore diameters of 20-200nm. When evaluated as cathode materials for pseudocapacitive hybrid batteries, the Co3O4 nanoflake microspheres deliver a specific capacity of 83mAhg−1 at 1Ag−1 after 10,000 cycles, higher than the Co3O4 nanowire microspheres counterpart (70mAhg−1). In addition, the electrode exhibits excellent long-term cycling stability with 94.5% capacity retention after 10,000 cycles at 1Ag−1. The enhancement of high-rate electrochemical performances is due to the unique nanoflake microspheres architecture with large surface area and open porous structure.
Force steadiness is a quantitative measure of the ability to control muscle tonus. It is an independent predictor of functional performance and has shown to correlate well with different degrees of motor impairment following stroke. Despite being clinically relevant, few studies have assessed the validity of measuring force steadiness. The aim of this study was to explore the reproducibility of handgrip force steadiness, and to assess age difference in steadiness.
Li metal batteries offer much hope for the future of high-energy storage systems. Albertus et al. survey the current status of research and commercial efforts, and discuss key metrics and measurements as well as cost issues in enabling high-performing lithium metal electrodes.
The goal of the present research was to study the content and types of childhood fears of primary schoolchildren living in urban and rural areas. 72 children aged between 7 and 8 (42 children live in Kazan, 30 children live in the country) took part in the experimental research carried out for this purpose.The battery of tests was used for the data collection. The obtained results were exposed to statistic processing. It was found out that urban children have bigger quantity of fears than rural schoolchildren. They experience the fear of assault, they are afraid of strangers, transport, open space and sleep. Rural children are afraid of pain, sharp sounds, fairy-tale characters. Primary schoolchildren with a high level of anxiousness have more than 20 types of fears. The article presents some recommendations for children's fears correction.
Expensive Pt-based catalysts are usually required to achieve a high discharge voltage and long operation life for hybrid Li-air batteries. However, the cost of the catalysts needs to be lowered by either reducing the Pt loading in the catalysts or replacing Pt with less expensive catalysts. Here, we report the strong coupling of Co3O4 nanocrystals with an O- and N-doped carbon nanoweb (ON-CNW) as a low-cost, highly-efficient catalyst for hybrid Li-air batteries with an alkaline catholyte. Co3O4/ON-CNW greatly reduces the discharge overpotential compared to ON-CNW and exhibits longer cycle life, which is even better than that of the best reported N-doped mesoporous carbon (0.016% decrease in efficiency per cycle for 130 cycles compared to 0.017% decrease per cycle for 100 cycles obtained with N-doped mesoporous carbon). Although Pt/C exhibits a slightly higher initial discharge voltage (3.02V compared to 3.00V for Co3O4/ON-CNW), the cycle life of Pt/C is<50 cycles, making Co3O4/ON-CNW as a viable, stable cathode for hybrid Li-air batteries.
The electrocatalytic characteristics of a metal hydride (MH) electrode for advanced Ni/MH batteries include the hydrogen adsorption/desorption capability at the electrode/electrolyte interface. The hydrogen reactions at the MH electrode/electrolyte interface are also related to factors such as the surface area of the MH alloy powder and the nature of additives and binder materials. The high-rate discharge capability of the negative electrode in a Ni/MH battery is mainly determined by the mass transfer process in the bulk MH alloy powder and the charge transfer process at the interface between the MH alloy powder and the electrolyte. In this study, an AB5-type hydrogen-absorbing alloy, Mm (Ni, Co, Al, Mn)5.02 (where Mm denotes Mischmetal, comprising 43.1wt.% La, 3.5wt.% Ce, 13.3wt.% Pr and 38.9wt.% Nd), was used as the negative MH electrode material. The MH electrode was charged and discharged for up to 200 cycles. The specific discharge capacity of the alloy electrode decreases from a maximum value of 290–250mAhg−1 after 200 charge/discharge cycles. A cyclic voltammetry technique is used to analyze the charge transfer reactions at the electrode/electrolyte interface and the hydrogen surface coverage capacity.
Nakazawa and colleagues describe a mouse strain in which the NR1 subunit of the NMDA receptor is selectively eliminated in cortical and hippocampal interneurons in early postnatal development. These mice have several behavioral deficits that are consistent with the theory that GABAergic dysfunction contributes to the pathology of several psychiatric disorders, including schizophrenia.
Internet of Things is based on the identification of real-world objects in a unique way that interconnects them by means of communication interfaces. Such a simple idea allows the emergence of a huge number of new applications in almost any domain of knowledge. One of the most prominent areas of application is road vehicles, which currently have, on average, more than 50 sensors inside and which information can be accessed through a standard protocol. With this, vehicles have become real smart objects that can interact with other objects or any software system. To allow that, our previous work focused on proposing and developing the Vitruvius platform, where users with no programming knowledge can design and quickly generate Web applications based on the real-time data consumption from interconnected vehicles. The problem is that the sending of such information is out of control, being unable to filter out when the best time to send the information is and what information should be sent at any moment in order to minimize the resource consumption of the mobile device that acts as a bride between the vehicle and the database in which all the information is stored. Thus, in this work we propose a fuzzy algorithm that allows to optimize the resources that are used by real-time applications that constantly send data while maintaining data quality, contextualized in vehicle sensor tracking systems and the applications that can be built above them.
The SnO2@polypyrrole (PPy) nanocomposites have been synthesized by a one-pot oxidative chemical polymerization method. The structure, composition, and morphology of the as-prepared SnO2@PPy nanocomposites are characterized by XRD, FTIR, TG, SEM, and TEM. Electrochemical investigations show that the obtained SnO2@PPy nanocomposites exhibit high discharge/charge capacities and favorable cycling when they are employed as anode materials for rechargeable lithium-ion batteries. For the SnO2@PPy nanocomposite with 79wt% SnO2, the electrode reaction kinetics is demonstrated to be controlled by the diffusion of Li+ ions in the nanocomposite. The calculated diffusion coefficiency of lithium ions in the SnO2@PPy nanocomposite with 79wt% SnO2 is 6.7×10−8 cm2 s−1, while the lithium-alloying activation energy at 0.5V is 47.3kJmol−1, which is obviously lower than that for the bare SnO2. The enhanced electrode performance with the SnO2@PPy nanocomposite is proposed to derive from the advantageous nanostructures that allow better structural flexibility, shorter diffusion length, and easier interaction with lithium.
Chitosan (CS) nanofibers were successfully used to modify indium tin oxide (ITO) electrode by electrospinning technique. Then, Prussian blue (PB) nanoparticles were electrodeposited on the CS nanofibers by potentiostatic technique in an acidic solution containing single ferricyanide. By this method, direct synthesis of PB nanoparticles on the nanofibers that were used for modifying electrode came true. Transmission electronic microscopy (TEM) showed that the average size of PB nanoparticles was about 50nm. Selected-area electron diffraction (SAED) showed diffusive diffraction spots, indicating the mosaic structure of the PB nanoparticles on the CS nanofibers. X-ray powder diffraction (XRD) displayed the long-range disorder of CS nanofibers and demonstrated the formation of PB nanoparticles. Results of the scanning electron microscope (SEM) images indicated that the PB nanoparticles could be electrodeposited on the CS nanofibers. The amount of the PB nanoparticles on the CS nanofibers increased with increasing potential value of the electrodeposition. In addition, the cyclic voltammetric response displayed two characteristic redox couples of PB. The modified electrode exhibited electrocatalytic activity towards reduction of H2O2.
The history, current state, surveys, and prospects of development of helioenergy in Poland have been presented. In general, Poland has relatively good conditions for the development of helioenergy, which are comparable to those of Germany. The achievements of Jan Czochralski, known as the father of photovoltaics, have also been described. The indicator of total installed area of solar collectors per number of inhabitants in Poland reached 39.0m2/1000 people at the end of 2013. The Polish solar collector market is the second largest in Europe. Currently there are 193 photovoltaic power stations of total power of 35.6MW (electricity for 480 households) operating in Poland. According to surveys, the owners of companies installing flat plate solar collectors or flat plate and evacuated tube solar collectors in Poland are satisfied with their turnover. Solar collectors of efficiency of about 80% and surface area of 1.9–2.44m2 are the most often sold. The photovoltaic modules that are the most often sold in Poland are the modules of efficiency of 12–15% and power of about 250W. In the near future a further rise in the number of installed solar collectors is forecast and large photovoltaic power stations are also planned. The total potential of thermal solar power in Poland is estimated to be about 19PJ/year (heat for 590,000 households) in 2020.
Dual-porous Ge nanostructures are synthesized via two straightforward steps. Compared with conventional approaches related to porous Ge materials, different types of pores can be readily generated by adjusting the relative ratio of the precursor amounts for GeO2 and SiO2. Unlike using hard templates with different sizes for introducing secondary pores, this system makes a uniformly blended structure of porogen and active sites in the nanoscale range. When GeO2 is subjected to zincothermic reduction, it is selectively converted to pure Ge still connected to unreacted SiO2. During the reduction process, primary pores (larger than 50 nm) are formed by eliminating zinc oxide by-products, while inactive SiO2 with respect to zinc metal could contribute to retaining the overall structure. Finally, the HF treatment completely leaches remaining SiO2 and formed secondary pores (micro/mesopores) to complete the dual-porous Ge structure. The resulting Ge structure is tested as an anode material for lithium-ion batteries. The Ge electrode exhibits an outstanding reversibility and an exceptional cycling stability corresponding to a capacity retention of 100% after 100 cycles at C/5 and of 94.4% after 300 cycles at C/2. Furthermore, multi-scale pores facilitate a facile Li-ion accessibility, resulting in an excellent rate capability delivering ∼740 mAh g−1 at 5C.
Current trends in battery research are promoting the development of feasible methods to prepare electrode materials with new architectures that can meet the requirements of high energy density associated with sodium ion batteries (SIB). It is logical to use solid-state processing techniques to fabricate SIB electrode materials due to its ease of handling and capability for large-scale production. From the SIB standpoint, the sulfate based polyanionic system is well known for its high operating voltage. The present study utilizes a hitherto-unknown solid-state process with an entirely new composition to develop an electrode comprising earth abundant carbon, sodium, sulfur, fluorine, and iron materials. This new NaFeSO4F-CNT system, where CNT is carbon nanotube, obtained by the solid-state technique, exhibits a highly stable Fe2+/Fe3+ redox couple and achieves a capacity of ∼110 mAg−1 at 0.1C with capacity retention of >91% after 200 cycles (1C). This is the best-ever reversible, high potential sulfate based cathode for sodium ion batteries reported to date. This study also provides an in-depth understanding of the outstanding electrochemical performance of this novel electrode. These findings can make it possible to achieve maximum performance from potential electrodes, when the operating temperature is limited to 350 °C or below.
The direct borohydride fuel cell (DBFC) is a fuel cell for which there is consensus about its promising commercial future as a portable power system. However, its development faces three main issues: the borohydride hydrolysis (issue 1) and crossover (issue 2), and the cost (issue 3). These issues are encountered by the membrane–electrodes-assembly. By a discussion around these three issues, the present paper reviews the experimental aspects. The discussion stresses on the opportunities of improvements and reviews the potential solutions that are proposed in the open literature. For each issue, the best solution seems to be a combination of improvements. The issue 1 may be solved thanks to a gold-based anode catalyst and an optimized fuel. The solution to the issue 2 may be a more efficient membrane combined with an optimized fuel and an inactive-towards-borohydride cathode catalyst like MnO2. Regarding the issue 3, cheaper materials and better fuel use efficiency are the keys. The DBFC is still in a development phase with a small number of years of R&D invested and it appears that there are real improvement opportunities on the path of the DBFC marketing.
A group of valve-regulated lead–acid (VRLA) batteries (12V, 33Ah) cycled under high power has exhibited premature failure. The only difference between failed and healthy batteries is the shedding of active material from the positive plates. The dislodged material has been examined by means of X-ray diffraction, scanning electron microscopy, and cyclic voltammetry. It is found that the material has a β-PbO2 structure. The particles, which are oval in shape with a diameter of about 100μm, are uniform and well separated from each other. The activity of the material can be restored under pressure. It is concluded that the failure mode of VRLA batteries under high-power cycling is softening of the positive active-material, which eventually results in deterioration of the electrical conductivity and de-activation of the material.