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Porous hard carbon with good cycling durability attracts much attention in the application of sodium ions batteries as anode material, but the commonly used alkali metal ion-activation strategy with complex processes still renders its development. Herein, a simple and scalable method is proposed to synthesize hierarchical porous hard carbon. Benefitting from the efficient self-activation strategy, the hierarchical micro–mesoporous hard carbon (MMHC) with large interlayer distance possesses high specific surface area of 704.1 m2 g−1, which can provide shorter ionic diffusion path and much more accessible electrochemical active sites in the carbonaceous structure and then lead to fast sodium ion diffusivity kinetics (3.5 × 10–9 cm2 s−1). In consequence, MMHC electrode delivers high specific capacity of 214.3 mAh g−1 at 50 mA g−1, 118.3 mAh g−1 at 500 mA g−1 after 1000 cycles and 47.4 mAh g−1 even at 4000 mA g−1. Notably, the capacity contribution ratio from low-voltage range is enhanced with engineering micro–mesoporous structure (from 28.5% for HC to 37.7% for MMHC). Promisingly, the hierarchical micro–mesoporous hard carbon holds great potential in commercial sodium ions batteries. [ABSTRACT FROM AUTHOR]

MoS2 nanosheets consist of multiple S-Mo-S trilayers with large interlayer spacing, which could allow facile Li-ion insertion/extraction. However, MoS2 nanosheets are easily curled and randomly stacked due to high surface energy of 2D nanosheets, which hinders fast ion transportation. In addition, intrinsic electronic conductivity of MoS2 is limited. Therefore, enhancements of both ionic and electronic conductivity of MoS2 are greatly demanded for its application in Li-ion batteries. Here, we report a cost-effective and facile hydrothermal synthesis of 3D nanoflower-like MoS2/C anode materials, which avoids random stacking of nanosheets and improves the electronic conductivity of MoS2. The nanoflower-like MoS2/C exhibits large reversible specific capacity (724 mAh g−1) and high initial coulombic efficiency (79.82%). Moreover, excellent capacity retention (97.98%) after 500-cycle charge/discharge has been achieved at 1 A g−1. [ABSTRACT FROM AUTHOR]

To measure the high-energy part of the energy distribution function of ions in a hot plasma using the pellet charge exchange (PCX) diagnostic, it is necessary to know the energy dependence of the fraction F0(E) of fast ions neutralized when intersecting a pellet cloud. Using experimental and calculated data on the ablation of polystyrene macroparticles (pellets) in the LHD stellarator, the function F0(E) for protons in the hydrocarbon cloud has been calculated in the energy range of 50–1000 keV at pitch angles . At energies of 50‒200 keV, it is necessary to take into account the decrease in the flux of neutralized protons multiply intersecting the cloud. Energy losses of protons along the trajectory provide a lower bound E > 100 keV for the possible PCX measurements. The necessity of the control of the charge state composition and structure of the cloud limits the view area of the detector of atoms within ±30 mm from the position of a pellet along the magnetic field. For this reason, the injection axis should be aligned with the observation axis of the neutral particle analyzer for the optimal geometry of PCX measurements with polystyrene pellets. [ABSTRACT FROM AUTHOR]

The phenomenon known as strong thermal emission velocity enhancement (STEVE) is a purple/mauve arc-shaped atmospheric glow observed at lower latitudes of the auroral oval on the duskside. Simultaneous observations using a ground-based camera and a low-altitude satellite have shown that STEVE is accompanied by rapid westward ion flows. Such fast ion flows are termed the subauroral ion drift (SAID) or subauroral polarization stream (SAPS). Similarly, an eastward fast ion flow known as the dawnside auroral polarization stream (DAPS) is observed within the Region 1 current on the dawnside. If the optical phenomenon triggered by SAID/SAPS corresponds to STEVE, a comparable optical phenomenon should be driven by DAPS. Thus far, however, such a phenomenon has not been reported. This study discovers, for the first time, a purple-colored optical phenomenon characterized by the fast eastward ion flows, a possible signature of DAPS, occurring poleward of the bright green arc in the post-midnight sector. We present color all-sky images obtained by a ground-based commercial digital camera, along with wide-coverage optical measurements and in-situ data from low-altitude satellites. The results imply that this glow requires not only a high-speed ion flow but also its sharp latitudinal gradient at the boundary between the Region 1 and 2. [ABSTRACT FROM AUTHOR]

Improving the electrochemical performance of electrode materials via structural design is critical in developing energy storage technologies. In this investigation, a nanoarray electrode composed of Co–Ni layered double hydroxide (Ni–Co LDH) nanosheets and Ni2SnO4 nanosheets (Ni2SnO4 NSs) stabilized on Ni foam (NF) is developed utilizing an in-situ growth method to its electrochemical properties in supercapacitors can be evaluated. The Ni2SnO4 was created in the first stage using a light hydrothermal reaction as the core. The Ni–Co LDH was then hydrothermally immobilized using the electrode, which had been made as a skeleton. The structural and textural study of the material was described using energy dispersive X-ray analysis (XRD), Fourier transforms infrared (FT–IR), field-emission scanning electron microscopy, and transmission electron microscopy. When the developed Ni–Co LDH/Ni2SnO4/NF electrode is compared to the Ni2SnO4/NF electrode, the electrochemical result shows a specific capacitance of up to 3,924 F g−1 at 1 A g−1 in a 2 mol L−1 KOH electrolyte, as well as a capacitance retention of 95% after 3000 cycles. Unsymmetrical supercapacitors made of Ni–Co LDH/Ni2SnO4/NF and activated carbon demonstrated exceptional electrochemical properties, including high rate capability, high energy, and power density (91.03 Wh kg−1 and 9.0 kW kg−1, respectively), and long cycle life. Due to its unique core/shell structural system, which facilitates ion diffusion and offers a fast electron transport kinetic model and good strain lodging, the rising pseudocapacitive behaviors render it an intriguing candidate for electrochemical energy storage. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) are required to possess long cycle life when used for large-scale energy storage. The polyanionic Na4MnV(PO4)3 (NMVP) reveals good cyclic stability due to its unique three-dimensional (3D) frame structure, but it still faces the challenge of interfacial degradation in practical applications. In this work, NASICON-type Na1.3Al0.7Ti1.3(PO4)3 (NATP) was deposited on the surface of NMVP to promote interface stability by surface modification and gradient doping. As a result, the optimized NMVP@2%NATP released a capacity retention of 44.8% after 1000 cycles at 5 C, much higher than that of the initial NMVP (28.9%). The enhanced electrochemical performance was mainly attributed to NATP coating acting as a fast ion transport carrier and physical barrier, significantly facilitating the Na+ diffusion and isolating side reaction at the electrode/electrolyte interface. On the other hand, Ti4+ and Al3+ cations from the NATP were partially doped inside the NMVP surface to boost the transport of Na+, and the perfect lattice matching of NVMP and NATP improved the interface and structural stability accompanying long cycling. This work demonstrated the effectiveness of surface modification with high lattice match material and provided new perspectives for high energy density solid-state SIBs. [ABSTRACT FROM AUTHOR]

Highlights: A molecular-sieving electrode coating towards low-concentrated aqueous sodium-ion batteries is constructed by applying a composite of NaX zeolite and NaOH-neutralized Nafion. Resulting from a molecular sieving effect of zeolite channels and size-shrunken ionic domains in Nafion, the as-prepared coating layer reject hydrated Na+ ions and allow fast dehydrated Na+ permeance. 200 cycles of Na2MnFe(CN)6//NaTi2(PO4)3 full cells can be achieved in a practically feasible 2 m aqueous electrolyte. Aqueous sodium-ion batteries are known for poor rechargeability because of the competitive water decomposition reactions and the high electrode solubility. Improvements have been reported by salt-concentrated and organic-hybridized electrolyte designs, however, at the expense of cost and safety. Here, we report the prolonged cycling of ASIBs in routine dilute electrolytes by employing artificial electrode coatings consisting of NaX zeolite and NaOH-neutralized perfluorinated sulfonic polymer. The as-formed composite interphase exhibits a molecular-sieving effect jointly played by zeolite channels and size-shrunken ionic domains in the polymer matrix, which enables high rejection of hydrated Na+ ions while allowing fast dehydrated Na+ permeance. Applying this coating to electrode surfaces expands the electrochemical window of a practically feasible 2 mol kg–1 sodium trifluoromethanesulfonate aqueous electrolyte to 2.70 V and affords Na2MnFe(CN)6//NaTi2(PO4)3 full cells with an unprecedented cycling stability of 94.9% capacity retention after 200 cycles at 1 C. Combined with emerging electrolyte modifications, this molecular-sieving interphase brings amplified benefits in long-term operation of ASIBs. [ABSTRACT FROM AUTHOR]

The CuO anode prepared by the traditional slurry coating method still suffers from limited lithium-ion transport kinetics due to the long diffusion lengths and tortuous transport paths resulting from the addition of conductive agents and binders. In this study, we have prepared the integrated CuO@Cu electrode with the porous CuO nanosheets in situ vertically grown on Cu current collector using a chemical etching method. The integrated electrode design improves the electrical conductivity of the electrode, and the porous nanosheets increase the contact area of the electrolyte and buffer the volume variation of CuO during cycling. Moreover, the vertically grown CuO nanosheets can shorten the lithium ion diffusion path and reduce the tortuosity of lithium ion transport pathways, thus realizing fast lithium ion storage kinetics. While the slurry coating CuO powder electrode shows a capacity of 13.3 mAh g−1 at 20 A g−1, our integrated CuO@Cu electrode still delivers a capacity of 181.6 mAh g−1 at 20 A g−1. This study demonstrates that rational structural design can significantly improve Li-ion storage kinetics. [ABSTRACT FROM AUTHOR]

Potassium-ion battery (PIB) is a potential candidate for future large-scale energy storage devices. Constructing electrode materials with fast ions and electron transport channels is an effective solution to achieve high-power-density and long-cycle PIBs. Herein, the composite composed of FeS quantum dots and nitrogen-doped porous carbon (FeS@NPC) is reported as anode material for PIBs. The unique uniform nanostructure is confirmed to be able to reduce the ion diffusion length, increase the migration rate of potassium ions, improve electronic conductivity, and alleviate volume fluctuation. These advantages deliver enhanced potassium storage properties with high capacity and excellent cycling stability. FeS@NPC-based anode obtains a specific capacity of 224 mAh g−1 at 1 A g−1 and 180 mAh g−1 at 5 A g−1 even after 1200 cycles. [ABSTRACT FROM AUTHOR]

Li metal batteries using Li metal as negative electrode and LiNi1-x-yMnxCoyO2 as positive electrode represent the next generation high-energy batteries. A major challenge facing these batteries is finding electrolytes capable of forming good interphases. Conventionally, electrolyte is fluorinated to generate anion-derived LiF-rich interphases. However, their low ionic conductivities forbid fast-charging. Here, we use CsNO3 as a dual-functional additive to form stable interphases on both electrodes. Such strategy allows the use of 1,2-dimethoxyethane as the single solvent, promising superior ion transport and fast charging. LiNi1-x-yMnxCoyO2 is protected by the nitrate-derived species. On the Li metal side, large Cs+ has weak interactions with the solvent, leading to presence of anions in the solvation sheath and an anion-derived interphase. The interphase is surprisingly dominated by cesium bis(fluorosulfonyl)imide, a component not reported before. Its presence suggests that Cs+ is doing more than just electrostatic shielding as commonly believed. The interphase is free of LiF but still promises high performance as cells with high LiNi0.8Mn0.1Co0.1O2 loading (21 mg/cm2) and low N/P ratio (~2) can be cycled at 2C (~8 mA/cm2) with above 80% capacity retention after 200 cycles. These results suggest the role of LiF and Cs-containing additives need to be revisited. Fluorinated interphases are often pursued as a design strategy for Li metal batteries. In contrast, here the authors show that an electrolyte with a non-fluorinated solvent and CsNO3 additive results in an LiF-free but inorganic-rich interphase that enables fast-charging of Li metal batteries. [ABSTRACT FROM AUTHOR]

The statistical method is applied to calculate the new channel of radiative losses of alpha particles, deuterons, and tritons when exciting multielectron impurity ions in thermonuclear plasma. A new statistical model of Coulomb–Born atom excitation is elaborated accounting for the normalization of transition probabilities. The radiative losses of multielectron tungsten ions are calculated within the scope of two statistical plasma models—local plasma frequency (LPF) and Coulomb–Born models. The results of both models are in a good agreement with each other; the sum of the radiative losses of fast heavy ions are of the same order of magnitude as those of electrons, including bremsstrahlung and radiative and dielectronic recombination. [ABSTRACT FROM AUTHOR]

Absorbed power of the neutral-injection beam in spherical tokamaks Globus-M/M2 is estimated numerically. Deceleration of fast particles is simulated by means of the NUBEAM code. The signal of analyzer of charge-exchange atoms is simulated by means of the FIDASIM code using the distribution function of fast ions calculated by means of the NUBEAM code. Comparison of calculated and experimental signals allowed determining the degree of influence of instabilities on confinement of fast particles along with absorbed beam power. [ABSTRACT FROM AUTHOR]

The results of experiments are described, which were performed at the Globus-M2 tokamak and aimed at studying the fast ion loss at the outer tokamak wall due to fast ions interaction with the toroidal Alfvén eigenmodes. The local heating of carbon tiles was experimentally measured, and the corresponding heat flux was calculated. It was shown how simulations of the lost particle orbits can explain the characteristic features of the spatial map of wall heating. The flux of lost fast particles onto the wall was studied as a function of the instability amplitude. It has been demonstrated that the simulations predict similar dependence of the fast ion flux on the instability amplitude and also correlate its nature to the peculiarities of fast ions spatial distribution. [ABSTRACT FROM AUTHOR]

With an increase of magnetic field up to 0.8 T and plasma current to 400 kA, fast ion losses rate in the discharges with toroidal Alfven eigenmodes decreased in tokamak Globus-M2 comparing with Globus-M tokamak discharges. Taking into account the data on the discharges with increased magnetic field and plasma current, the regression fit of neutral particle analyzer flux drop in energy channel close to neutral beam energy on relative eigenmode magnitude, the value of magnetic field and plasma current was analyzed. The power of flux drop dependence on TAE magnitude was found to be ~0.5 and inverse proportional on the value of product of magnetic field and plasma current, which is highly likely is determined only by plasma current due to weak dependence on magnetic field. The result obtained indicates that fast ion losses in Globus-M2, stimulated by toroidal Alfven eigenmodes are mostly determined by the shift of passing orbits to the plasma edge. With the increase of plasma current and magnetic field, neutron flux drops arising in the moments of toroidal mode bursts have also decreased. [ABSTRACT FROM AUTHOR]

The thermonuclear fusion between fast (super-thermal) particles injected in plasma as a neutral beam and the ions of the background plasma is expected to be the main source of fusion neutrons in FNS (fusion neutron source) design based on tokamak. Neutral beam contribution in fusion reactivity and in the total neutron yield depends on the high-energy ion fraction in the integral energy distribution. NESTOR code [1] calculates nuclear fusion rates in the FNS plasma volume, taking into account an external source of high-energy fast ions. Neutral beam model reproduces in detail the actual beam structure in phase space at the injection port plane; while the fast ion distributions in magnetically confined plasma are calculated using a combination of slowing-down classical formulae and magnetic field topology in the tokamak chamber. Here we discuss the issues relevant to the overall neutron production and the contribution of fast ions to the neutron output in plasma. [ABSTRACT FROM AUTHOR]

The templating method holds great promise for fabricating surface nanopatterns. To enhance the manufacturing capabilities of complex surface nanopatterns, it is important to explore new modes of the templates beyond their conventional masking and molding modes. Here, we employed the metal-organic framework (MOF) microparticles assembled monolayer films as templates for metal electrodeposition and revealed a previously unidentified guiding growth mode enabling the precise growth of metallic films exclusively underneath the MOF microparticles. The guiding growth mode was induced by the fast ion transportation within the nanochannels of the MOF templates. The MOF template could be repeatedly used, allowing for the creation of identical metallic surface nanopatterns for multiple times on different substrates. The MOF template-guided electrochemical growth mode provided a robust route towards cost-effective fabrication of complex metallic surface nanopatterns with promising applications in metamaterials, plasmonics, and surface-enhanced Raman spectroscopy (SERS) sensing fields. Templating method holds great promise for fabricating surface nanopatterns. Here authors present a guiding growth mode using metal-organic framework microparticles as templates during metal electrodeposition, where metals exclusively grow underneath the microparticles. [ABSTRACT FROM AUTHOR]

In situ formation of a stable interphase layer on zinc surface is an effective solution to suppress dendrite growth. However, the fast transport of bivalent Zn-ions within the solid interlayer remains very challenging. Herein, we engineer the SEI components and enable superior kinetics of Zn metal batteries under harsh conditions through regulating the sequence of interfacial chemical reaction. With the differences in chemical reactivity of trimethyl phosphate co-solvent and trifluoromethanesulfonate anions in the Zn2+-solvation shell, Zn3(PO4)2 and ZnF2 are successively generated on Zn metal surface to form a gradient ZnF2–Zn3(PO4)2 interphase. Mechanistic studies reveal the outer ZnF2 facilitates Zn2+ desolvation and inner Zn3(PO4)2 serves as channels for fast Zn2+ transport, contributing to long-term cycling at subzero temperatures. Impressively, the gradient SEI enables a high lifespan over 7000 hours in Zn symmetric cell and a capacity retention of 86.1% after 12000 cycles in Zn–KVOH full cell at –50 °C. Zinc batteries have received intense attentions but suffer from inferior low-temperature performance. Here, the authors constructed a gradient phosphatized interphase in situ on zinc surface to accelerate zinc-ion desolvation and transport, greatly enhancing the cycling performance at subzero temperatures. [ABSTRACT FROM AUTHOR]

A theoretical method for evaluating the single-electron capture (SEC) cross sections in collisions of fast ions with a ground-state H2 molecule is presented. The scattering problem for ion-molecule collisions is formulated in the impact parameter representation using the relation between the quantum-mechanical amplitude and quasi-classical impact parameter one. The capture amplitudes and corresponding probabilities of capture to (nlm) states of an incident ion are derived within the framework of the Brinkman–Kramers approximation. The general expressions for the SEC probability amplitudes to n-states, summed over l and m quantum numbers, are deduced, from which the corresponding SEC probabilities can be then calculated using a procedure of multichannel normalization. The dependence of the differential cross sections, integrated over projectile impact parameters, on the molecular orientation for charge exchange in H+ + H2 collisions is considered and compared with measurements and other calculations. Total SEC cross sections, integrated over the molecular orientations and summed over n-states for several bare and dressed ions, are calculated and compared with available experimental data and results of calculations by means of other theoretical methods. [ABSTRACT FROM AUTHOR]

Solid polymer electrolytes (SPEs) and hydrogel electrolytes were developed as electrolytes for zinc ion batteries (ZIBs). Hydrogels can retain water molecules and provide high ionic conductivities; however, they contain many free water molecules, inevitably causing side reactions on the zinc anode. SPEs can enhance the stability of anodes, but they typically possess low ionic conductivities and result in high impedance. Here, we develop a lean water hydrogel electrolyte, aiming to balance ion transfer, anode stability, electrochemical stability window and resistance. This hydrogel is equipped with a molecular lubrication mechanism to ensure fast ion transportation. Additionally, this design leads to a widened electrochemical stability window and highly reversible zinc plating/ stripping. The full cell shows excellent cycling stability and capacity retentions at high and low current rates, respectively. Moreover, superior adhesion ability can be achieved, meeting the needs of flexible devices. Excess water in hydrogel-based zinc ion batteries causes side reactions, but reduced water content results in low conductivities. Here, authors develop a lean-water hydrogel based on molecular lubrication mechanism for fast ion transportation, extended stability, and reversible Zinc plating/stripping. [ABSTRACT FROM AUTHOR]

Vanadium oxides have attracted extensive interest as electrode materials for many electrochemical energy storage devices owing to the features of abundant reserves, low cost, and variable valence. Based on the in-depth understanding of the energy storage mechanisms and reasonable design strategies, the performances of vanadium oxides as electrodes for batteries have been significantly optimized. Compared to crystalline vanadium oxides, amorphous vanadium oxides (AVOs) show many unique properties, including large specific surface area, excellent electrochemical stability, lots of defects and active sites, fast ion kinetics, and high elasticity. This review gives a comprehensive overview of the recent progress on AVOs for different energy storage systems, such as alkali metal ion batteries, multivalent ion batteries, and supercapacitors with a special focus on the preparation strategies. The basic mechanisms for energy storage performance improvements of AVOs as compared to their crystalline counterparts are also introduced. Finally, challenges faced by AVOs are discussed and future development prospects are also proposed. This review aims to provide a comprehensive knowledge of AVOs and is expected to promote the development of high-performance electrodes for batteries. [ABSTRACT FROM AUTHOR]

The development of electrode materials plays a vital role in energy storage applications to save and store energy. In the present work, the synthesis of nanorod shaped Mn3O4 supported with amorphous carbon (Mn3O4/AC) is reported by the microwave method for supercapacitor application. The as-prepared electrode material was then characterized using microscopic and spectroscopic techniques. The electrochemical supercapacitor performance of Mn3O4/AC was examined by the cyclic voltammetry and galvanostatic charge–discharge method inside the three-electrode assembly cell. The results showed that the Mn3O4/AC delivers the excellent capacitance value of the 569.5 Fg−1 at the current load of 1 Ag−1, higher than the previously reported Mn3O4 based electrodes. The better performance of the Mn3O4/AC is credited to the excellent redox behaviour of the Mn3O4 and the presence of the amorphous carbon, which facilitated the fast ion interaction between the electrode and electrolyte during the electrochemical reaction. [ABSTRACT FROM AUTHOR]

The stopping power of charged particles released by the deuterium–tritium nuclear reactions has been extensively studied in the weakly to moderately coupled plasma regimes. We have modified the conventional effective potential theory (EPT) stopping framework to have a practical connection to investigate the ions energy loss characteristics in fusion plasma. Our modified EPT model differs from the original EPT framework by a coefficient of order 1 + 2 / (5 ln Ξ ¯) , ( ln Ξ ¯ is a velocity-dependent generalization of the Coulomb logarithm). Molecular dynamics simulations agree well with our modified stopping framework. To study the role of related stopping formalisms in ion fast ignition, we simulate the cone-in-shell configuration under laser-accelerated aluminum beam incidence. In ignition/burn phase, the performance of our modified model is in agreement with its original form and the conventional Li-Petrasso (LP) and Brown-Preston-Singleton (BPS) theories. The LP theory indicates the fastest rate in providing ignition/burn condition. Our modified EPT model with a discrepancy of ∼ 9%, has the most agreement with LP theory, while that of the original EPT (with a discrepancy of ∼ 47% to LP) and BPS (with a discrepancy of ∼ 48% to LP) methods maintain the third and fourth contributions in accelerating the ignition time, respectively. [ABSTRACT FROM AUTHOR]

Ni-rich layered cathode materials LiNixCoyMn(1-x–y)O2 (x ≥ 0.8) suffer from capacity decay due to structural deterioration during electrochemical cycling. To overcome these problems, the fast-ion conductor Li0.33La0.56TiO3 (LLTO) is coated on the surface of LiNi0.83Co0.12Mn0.05O2 (NCM83) cathodes through the sol–gel method, which can stabilize the electrode/electrolyte interface of cathode materials and facilitate Li+ transport and charge transfer. As a result, the LLTO-coated NCM83 exhibits better cycle stability and higher rate performance. The NCM83 modified by 5 wt% LLTO has the discharge capacity of 185.9 mAh g−1 at 1C rate after 100 cycles and with higher capacity retention of 92.9% than the pristine NCM83 of 86.2%, and as well as the 5 wt% LLTO-coated NCM83 has a higher Li+-insert diffusion coefficient of 1.143 × 10−11 cm2 s−1 than the pristine NCM83 of 8.757 × 10−12 cm2 s−1. Therefore, the fast-ion conductor LLTO coating strategy shows great potential in improving the performance of Ni-rich layered cathode materials. [ABSTRACT FROM AUTHOR]

In the 1990s, polymer-in-salt electrolytes (PISEs) came into the picture with the hope to overcome the problem of slow ion motion and low cation transference number in salt-in-polymer-electrolytes (SIPEs). The present paper reports an electrolyte membrane in the PISE range using renewable polymer (rice starch), synthesized using a simple solution cast technique having high moisture content (~ 12%). The synthesized flexible PISE membrane has high conductivity (~ 10−2 S/cm) and fast ion transport (relaxation time ~ µs). Conductivity is almost independent of relative humidity indicating the water molecules available in the matrix are involved in the lattice formation and the matrix is stable. X-ray diffraction (XRD) analysis and optical photographs have confirmed that the crosslinked starch matrix accepts a large amount of salt, and even at 300 wt% of salt (i.e., at 3:1 salt: starch ratio), morphology remains homogenous, and no signature of salt is present in XRD spectra. The electrochemical stability window (ESW ~ 2.7 V) is also wide enough for energy device fabrication. To check its potential for supercapacitor application, the two most simple electrodes (anodized Al and carbon cloths) were selected. The approximate rectangular shape of cyclic voltammetry (CV) performed at different scan rates from 5 to 500 V/s, indicated the EDLC-type charge storage phenomenon in the studied voltage ranges. For scan rate above 300 V/s, the capacitance value is almost independent of scan rate. All these indicate that crosslinked starch-based PISEs are a successful step towards the target for possibilities of commercial application of polymer-in-salt electrolytes. [ABSTRACT FROM AUTHOR]

Phase pure lithium trivanadate (LiV3O8) was synthesized by an ultrasound-assisted rheological phase reaction method for aqueous supercapacitor applications. The precursor was exposed to ultrasound for different time periods of 2, 6 and 10 h and then calcined under similar conditions. The effects of ultrasound on the structural features of the synthesized samples was characterized by XRD, and FTIR spectroscopy and the morphological features by SEM analysis. The sample synthesized by exposing the precursor to ultrasound for 10 h showed a high value of d100spacing, which facilitated the lithium (Li+) ion movement. Also, the formation of rod-like structures by the exposure of ultrasound facilitated the fast Li+ ion movement and enhanced the electrochemical performance. The electrochemical performance was measured using a three-electrode cell setup in the potential range of −0.8 to 0.2 V using 1 M LiNO3aqueous electrolyte. The specific capacitance of the material was found to be 120 F/g at a current density of 1A/g for the sample sonicated for 10 h (10S-LVO). The symmetric supercapacitor constructed using 10S-LVO showed the highest specific capacitance of 317F/g at 0.5 A/g, with 66.28% capacitance retention at 1A/g after 150 cycles. Effect of ultrasound on the morphology of LiV3O8 [ABSTRACT FROM AUTHOR]

Membranes with fast and selective ion transport are essential for separations and electrochemical energy conversion and storage devices. Metal-coordinated polymers are promising for fabricating ion-conducting membranes with molecular channels, however, the structures and ion transport channels remain poorly understood. Here, we reported mechanistic insights into the structures of metal-ion coordinated polybenzimidazole membranes and the preferential K+ transport. Molecular dynamics simulations suggested that coordination between metal ions and polybenzimidazole expanded the free volume, forming subnanometre molecular channels. The combined physical confinement in nanosized channels and electrostatic interactions of membranes resulted in a high K+ transference number up to 0.9 even in concentrated salt and alkaline solutions. The zinc-coordinated polybenzimidazole membrane enabled fast transport of charge carriers as well as suppressed water migration in an alkaline zinc-iron flow battery, enabling the battery to operate stably for over 340 hours. This study provided an alternative strategy to regulate the ion transport properties of polymer membranes by tuning polymer chain architectures via metal ion coordination. Membranes with fast and selective ion transport are essential for electrochemical processes. Here the authors provide mechanistic insights into the structures of metal-ion coordinated polybenzimidazole membranes and the preferential K+ transport, and their application in an alkaline zinc-iron flow battery. [ABSTRACT FROM AUTHOR]

Appropriate materials collaborated with reasonable structure can significantly increase the separator performance for lithium-ion batteries. In this work, taking the advantages of microfibrous and nanofibrous membranes and compensating for their defects, we developed a composited separator (GOPPH) with excellent overall performance by first wetting-modifying the polyethylene terephthalate microfibers and then laminating a polyvinylidene fluoride-hexafluoropropylene nanofiber layer. Such a combination not only offers the GOPPH separator, from the perspective of structure, with high porosity and hierarchical structure in terms of fiber diameter and pore size, but also provides satisfactory features including wettability, mechanical strength and thermal shutdown function that benefit from the selected materials. Meanwhile, as determined by experimental and theoretical approaches, the obtained GOPPH separator exhibits considerably enhanced lithium ion transport ability with a high lithium ion transference number and transport rate, which thereby endowing the cell with superior cycling stability with a capacity retention of 93% after 200 cycles at 1 C. Therefore, considering battery safety and performance, the GOPPH fibrous membrane could be a promising separator candidate for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

A fundamentally new approach for the deactivation of irradiated reactor graphite and metal structures of nuclear power plants is proposed, that is, a "dry" ion-plasma decontamination based on an interdisciplinary approach. The technology includes sputtering of a surface radioactive layer by fast ions of a microplasma discharge in an inert gas under atmospheric pressure with mass transfer in the diffusion mode and condensation of the sputtered material onto a replaceable collector anode. The experimental approbation of ion-plasma technology was carried out using samples of reactor graphite grade GR-280; the optimal operating parameters were obtained. [ABSTRACT FROM AUTHOR]

A project of a gamma-ray spectrometric system for diagnosing fast particles in the TRT tokamak plasma is described. The organizational concept of gamma spectrometric measurements is proposed. Preliminary results of calculating the intensities of gamma ray lines of hydrogen, deuterium, and deuterium–tritium plasmas are presented, which demonstrate the possibility of obtaining information about the energy and spatial distribution of fast ions with a time resolution of 1–10 s when using a multidetector system. Runaway electrons can be observed by hard X-ray emission from the tokamak plasma in the megaelectronvolt range. [ABSTRACT FROM AUTHOR]

A facile synthetic route based on the assistance of magnetic field is reported to fabricate core–shell CoB@Co(OH)2 nanochains for purpose of the high conductive pathway and enhanced pseudocapacitance in 3 M LiOH electrolyte. By adjusting the loading amount of the shell Co(OH)2 nanosheets anchored on the core CoB alloy surface, the typical core–shell CoB@Co(OH)2 is endowed with the appropriate pore volume of 0.27 cm3 g−1 and the high accessible electrode/electrolyte interfacial area (62.3 m2 g−1) and the fast conductive highway; meanwhile taking advantages of core–shell structure can be favor for fast ion transport between the electrode/electrolyte interphase and rapid electron transfer. Benefiting from the advantageous properties, the typical CoB@Co(OH)2 electrode exhibits a high specific capacitance of 492.8 F g−1 in three-electrode device together with good cyclic stability (90.4% capacitance retention) during continuously 5000 cycles at 2 A g−1. This work can provide an inspiring strategy for rational designing of core–shell CoB@Co(OH)2, and indicate their potential energy application in alkaline electrolyte. Core–shell CoB@Co(OH)2 electrode with rapid conductive highway achieves the broaden voltage of 0.8 V and the enhanced supercapacitive performance. [ABSTRACT FROM AUTHOR]

The results are presented from preliminary experiments on neutral beam injection with the power of approximately 1 MW into the central trap of the GOL-NB facility. The main technical task of the work was the integrated commissioning of all systems and basic diagnostics. The results are presented on the attenuation of neutral beams in plasma and the parameters of the fast ion population. In the regimes under discussion, the attenuation factor of the flow of injected particles of heating beams reaches 40% at the simultaneous start of the initial plasma accumulation in the trap and its heating by neutral beams. The dynamics of accumulation and energy spectrum of the fast ion population formed in plasma as a result of neutral beam injection are discussed, and the physical mechanisms are analyzed that can provide for the observed spectrum of fast ions. [ABSTRACT FROM AUTHOR]

Highlights: The composite gel electrolyte with low tortuosity ion-conducting arrays (GPE/ICAs) exhibiting high room-temperature ionic conductivity (1.08 mS cm−1) was successfully prepared by directionally growing ice crystals and in-situ polymerization. The stable and rapid Li+ migration through ICAs in the GPE is proved by 6Li solid-state nuclear magnetic resonance and synchrotron radiation X-ray diffraction combined with computer simulations. Li/LiFePO4 full cells using GPE/ICAs exhibit excellent cycle performance and high-capacity retention at wide temperature (0–60 °C), which has the potential towards all-weather practical solid-state batteries. The rapid improvement in the gel polymer electrolytes (GPEs) with high ionic conductivity brought it closer to practical applications in solid-state Li-metal batteries. The combination of solvent and polymer enables quasi-liquid fast ion transport in the GPEs. However, different ion transport capacity between solvent and polymer will cause local nonuniform Li+ distribution, leading to severe dendrite growth. In addition, the poor thermal stability of the solvent also limits the operating-temperature window of the electrolytes. Optimizing the ion transport environment and enhancing the thermal stability are two major challenges that hinder the application of GPEs. Here, a strategy by introducing ion-conducting arrays (ICA) is created by vertical-aligned montmorillonite into GPE. Rapid ion transport on the ICA was demonstrated by 6Li solid-state nuclear magnetic resonance and synchrotron X-ray diffraction, combined with computer simulations to visualize the transport process. Compared with conventional randomly dispersed fillers, ICA provides continuous interfaces to regulate the ion transport environment and enhances the tolerance of GPEs to extreme temperatures. Therefore, GPE/ICA exhibits high room-temperature ionic conductivity (1.08 mS cm−1) and long-term stable Li deposition/stripping cycles (> 1000 h). As a final proof, Li||GPE/ICA||LiFePO4 cells exhibit excellent cycle performance at wide temperature range (from 0 to 60 °C), which shows a promising path toward all-weather practical solid-state batteries. [ABSTRACT FROM AUTHOR]

Nowadays, electrolytes for commercial batteries are mostly liquid solutions composed of solvent and salt to migrate the ions. However, solvents of the electrolyte bring several inherent limitations, either the electrochemical window, working temperature, volatility or flammability. Herein, we report polyphosphoric acid as a solvent-free protic liquid electrolyte, which excludes the demerits of solvent and exhibits unprecedented superiorities, including nonflammability, wider electrochemical stability window (>2.5 V) than aqueous electrolyte, low volatility and wide working temperature range (>400 °C). The proton conductive electrolyte enables MoO3/LiVPO4F rocking-chair battery to operate well in a wide temperature range from 0 °C to 250 °C and deliver a high power density of 4975 W kg−1 at a high temperature of 100 °C. The solvent-free electrolyte could provide a viable route for the stable and safe batteries working under harsh conditions, opening up a route towards designing wide-temperature electrolytes. It is challenging to prepare electrolyte that could achieve wide electrochemical window, broad working temperature, non-inflammability, and fast ion transport simultaneously. Here the authors report a rocking-chair proton battery utilizing a solvent-free protic liquid electrolyte, which could operate in a broad temperature range from 0 to 250 celsius degree. [ABSTRACT FROM AUTHOR]

Kinetic approach to simulation of ion velocity (and energy) distribution function in the process of Z-pinch neck implosion, along with the energy spectrum of ions leaving the neck, are analyzed. A combination of acceleration in a magnetic field growing with time, Coulomb collisions, and losses determine the formation of ion spectrum within the framework of the kinetic Fokker–Planck equation. [ABSTRACT FROM AUTHOR]

To study the effect of the beam–plasma system geometry on current drive and generation of neutrons in plasma, an efficient model was used that combines the statistical description of the injected beam with the analytical methods for calculating particle trajectories. The calculation results were consistent with the classical models of interaction of neutral beams with plasma. The model presented is simple and high-performance that makes it possible to trace up to 1012 fast ions in plasma and quickly optimize the facility parameters with allowance for the plasma and beam geometry. It is shown that the dimensions and inner angular structure of the atomic beam considerably affect the process of fast ions capture in plasma and overall efficiency of neutral beam injection (NBI), including the current drive efficiency and generation rate of fusion neutrons during the interaction of fast ions with plasma ions. An example is presented of optimizing the NBI parameters for the FNS-C fusion neutron source based on the spherical tokamak. The current drive efficiency (NBI‑driven current) and neutron yield of the beam–plasma fusion reactions were chosen as target criteria for the system optimization. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cell (DSSC) technology could become a low-cost solution for solar energy harvesting if the use of expensive dyes and Pt can be avoided. This work reports the development of novel nanohybrid thin films based on CoNi2S4 nanotubes embedded on sheets of reduced graphene oxide (rGO), which can serve as an excellent counter electrode for DSSC showing great promise to replace Pt. The structural and morphological characterization of the nanocomposite films synthesized using a simple one-step hydrothermal method revealed well-defined crystalline nanotubes of CuNi2S4 (with length 200 nm and diameter 10.41 nm) uniformly embedded on the surfaces of the rGO sheets (~ 2.65 μm in size). The optimized CuNi2S4/rGO nanohybrid film when used as counter electrode in DSSC, photo conversion efficiency as high as 9.68 ± 0.02% was recorded, a value almost equal to that obtained from the DSSC fabricated with Pt as counter electrode (7.01 ± 0.01%) and much higher than that with bare CuNi2S4 (5.01 ± 0.01%) justifying its potential use in Pt-free DSSC. The improved performance of the electrode have been attributed to the hierarchical nanohybrid structure consisting of 1D CuNi2S4 nanotubes embedded on electrically conducting 2D rGO sheets that provides fast ion diffusion pathways, large accessible surface area and good chemical and thermal stability. [ABSTRACT FROM AUTHOR]

Lithium titanate composites with conducting additives are synthesized by the sol–gel method. As the conducting additives, carbon nanotubes (CNTs)—plain and heterosubstituted, graphene-like nanoflakes (CNFs), and the carbon coating formed by sucrose (S) pyrolysis are used. The introduction of carbon nanotubes considerably increases the reversible discharge capacity of composites including the case of high current densities. This occurs as a result of the formation of a three-dimensional network which sustains the fast transport of lithium ions and electrons between the particles of the anode material. Thus, at the current density of 200, 800, 1600, and 3200 mA/g, the reversible discharge capacity of the Li4Ti5O12/С/CNT is found to be 130, 107, 94, and 71 mA h/g, respectively. The use of CNFs as the conducting additive fails to considerably improve the properties of the anode material. [ABSTRACT FROM AUTHOR]

A scheme of a multichannel time-of-flight atomic analyzer with an electrostatic deflection system that provides two-dimensional focusing of the ion beam in the transverse direction is described. A thin carbon film with a thickness of 100 Å is used to ionize the incoming flow of atoms. The results of numerical simulation of the main parameters of the analyzer, such as the energy values in the channels, their energy resolution, and permeability, are given. An example of the possible use of such an atomic analyzer for measuring the energy distribution function of thermal plasma ions and fast ions of heating beams in the deuterium–tritium operating regime of the TRT facility is considered. The efficiency of radiation background suppression in the analyzer detection system by the coincidence circuit has been analyzed. [ABSTRACT FROM AUTHOR]

The applicability of neutral particle diagnostics for studying plasma parameters and additional methods of heating in the Tokamak with Reactor Technologies is analyzed. Options for the arrangement of diagnostic equipment, which includes three analyzers of charge-exchange atoms (neutral particle analyzers) for different energy ranges of recorded atomic fluxes, are given. It is shown that the diagnostic complex of analyzers makes it possible to measure the distribution functions of plasma thermal ions and to obtain information on the isotopic ratio of the main plasma ion component in the deuterium–tritium mode of facility operation. In addition, the proposed geometry of the analyzer arrangement makes it possible to measure the energy distribution of fast ions, which arise during neutral beam injection and ion cyclotron heating of plasma. [ABSTRACT FROM AUTHOR]

Ni3S2 nanosheets dual-doped with manganese, cobalt elements on conductive nickel foam (MC-Ni3S2) had been synthesized by two steps hydrothermal and directly applied as the electrode for high-performance electrochemical Supercapacitors (SCs). A plausible mechanism is proposed to explain the formation of the manganese, cobalt elements dual-doped Ni3S2 nanosheets. SCs electrodes based on the MC-Ni3S2 nanosheets are characterized and exhibit a specific capacitance of 2922 F g−1 (365.3 mAh g−1) at 2 A g−1. After 2000 cycles, it exhibited an excellent cycling stability owing to the unique nanosheets architecture providing fast ion/electron transfer. The fabricate approach may offer a new strategy for the synthesis of other mix transition metal sulfide for applications in supercapacitor. [ABSTRACT FROM AUTHOR]

Radioactive 129I with a long half-life (1.57 × 107 y) and high mobility is a serious radiohazard and one of the top risk radionuclides associated with its accidental and planned releases to nature. The complex speciation chemistry of iodine makes its removal a complicated task, and usually a single method is not able to remove all iodine species. Especially its oxidized form iodate (IO3−) lacks a selective and effective removal method. Here, the granular aggregates of hydrous zirconium oxides with and without antimony doping were tested for IO3− removal and the effects of contact time, competing anions in different concentrations and pH were examined. The materials showed high selectivity for IO3− (Kd over up to 50,000 ml/g) in the presence of competing ions and relatively fast uptake kinetics (eq. < 1 h). However, B(OH)4− and SO42−, as competing ions, lowered the iodate uptake significantly in basic and acidic solution, respectively. The suitability of the materials for practical applications was tested in a series of column experiments where the materials showed remarkably high apparent capacity for the IO3− uptake (3.2–3.5 mmol/g). [ABSTRACT FROM AUTHOR]

Aluminum particles are of significant interest in enhancing the energy release performance of explosives. One of the major impediments to their use is that Al2O3 shell significantly decreases overall performance. To address this issue, we investigate creating aluminum particles with a glycidyl azide polymer (GAP) coating to improve their reactivity while retaining their energy content. We found that the aluminum particles were coated with a GAP layer of thickness around 8.5 nm. The coated aluminum particles were compared to non-coated powder by the corresponding reactivity parameters obtained from simultaneous differential scanning calorimetry, thermal gravimetric analysis, coupled with mass spectral and infrared spectral analyses. Besides, the comparison on the energy content was also conducted based on P–t tests and a laser-induced air shock from energetic materials (LASEM) technique. It was found that GAP shifted the oxidation onset of aluminum particles to a lower temperature by ~ 10 °C. Besides, the oxidation activation energy of aluminum particles was also reduced by ~ 15 kJ mol−1. In return, aluminum particles reduced the activation energy of the second stage decomposition of the GAP by 276 kJ mol−1. And due to the synergistic effect between aluminum and GAP, the decomposition products of GAP were prone to be oxycarbide species rather than carbonitride species. In addition, the P–t test showed the peak pressure and pressurization rate of GAP coated aluminum particles were separately 1.4 times and 1.9 times as large as those of non-coated aluminum particles. Furthermore, the LASEM experiment suggested the shock wave velocity of the GAP coated aluminum particles was larger than that of non-coated aluminum particles, and the largest velocity difference for them could be 0.6 km s−1. This study suggests after coating by GAP, the aluminum particles possess enhanced reaction performance, which shows potential application value in the fields of aluminized explosives and other energetic fields. [ABSTRACT FROM AUTHOR]

Aiming development of the fast anion conductors, we proposed a new material design using flexible molecular cation as a host cation, and demonstrated it with fluoride ion conduction in NH4MgF3 and (NH4)2MgF4 based materials. Dominant fluoride ion conduction with relatively high conductivities of 4.8 × 10–5 S cm−1 and 8.4 × 10–6 S cm−1 were achieved at 323 K in (NH4)2(Mg0.85Li0.15)F3.85 and NH4(Mg0.9Li0.1)F2.9, respectively. It is implied that the molecular cation in the host lattice can assist the anion conduction. Our findings suggest molecular cation-containing compounds can be attractive material groups for fast anion conductors. [ABSTRACT FROM AUTHOR]

Optical chemosensors and ionochromic cellulosic papers based on oxazolidine chromophores were developed for selective photosensing of metal ions and information encryption as security tags, respectively. The oxazolidine molecules have been displayed highly intense fluorescent emission and coloration characteristics that are usable in sensing and anticounterfeiting applications. Obtained results indicated that oxazolidine molecules can be used for selective detection of pb2+ (0.01 M), and photosensing of Fe3+, Co2+ and Ag+ metal ion solutions by colorimetric and fluorometric mechanisms with higher intensity and sensitivity. Also, oxazolidine derivatives were coated on cellulosic papers via layer-by-layer method to prepare ionochromic papers. Prepared ionochromic papers were used for printing and handwriting of optical security tags by using of metal ion solutions as a new class of anticounterfeiting inks with dual-mode fluorometric and colorimetric securities. The ionochromic cellulosic papers can be used for photodetection of metal ions in a fast and facile manner that presence of metal ions is detectable by naked eyes. Also, key-lock anticounterfeiting technology based on ionochromic papers and metal ion solution as ink is the most significant strategy for encryption of information to optical tags with higher security. [ABSTRACT FROM AUTHOR]

The present study investigated the role of SiOx in a rice-husk-derived C/SiOx anode on the rate and cycling performance of a Li-ion battery. C/SiOx active materials with different SiOx contents (45, 24, and 5 mass%) were prepared from rice husk by heat treatment and immersion in NaOH solution. The C and SiOx specific capacities were 375 and 475 mAh g−1, respectively. A stable anodic operation was achieved by pre-lithiating the C/SiOx anode. Full-cells consisting of this anode and a Li(Ni0.5Co0.2Mn0.3)O2 cathode displayed high initial Coulombic efficiency (~ 85%) and high discharge specific capacity, indicating the maximum performance of the cathode (~ 150 mAh g−1). At increased current density, the higher the SiOx content, the higher the specific capacity retention, suggesting that the time response of the reversible reaction of SiOx with Li ions is faster than that of the C component. The full-cell with the highest SiOx content exhibited the largest decrease in cell specific capacity during the cycle test. The structural decay caused by the volume expansion of SiOx during Li-ion uptake and release degraded the cycling performance. Based on its high production yield and electrochemical benefits, degree of cycling performance degradation, and disadvantages of its removal, SiOx is preferably retained for Li-ion battery anode applications. [ABSTRACT FROM AUTHOR]

The electrode materials with long cycle life are important for the large-scale application of sodium ion batteries. In this work, P2-type Na0.71Co0.96-xTixO2 (x = 0, 0.057, 0.073, 0.09) were synthesized by molten-salt method. The Ti doping content could influence the crystallographic unit cell volume, particle size, oxygen vacancies, and surface charge density of those samples. When x = 0.073, the P2-type Na0.71Co0.96-xTixO2 (x = 0.073) exhibits superior reversible capacity and rate performance due to the appropriate synergistic effect. In particular, the initial discharge capacity of NCTO-0.073 is about 118.5 mAh g−1 at 100 mA g−1. Even the current density gets to 1000 mA g−1, the initial discharge capacity remains 71.7 mAh g−1 after 1000 cycling with the capacity retention of 67.90%. The electrochemical kinetics analysis further prove that the P2-type Na0.71Co0.96-xTixO2 (x = 0.073) owns outstanding electrical conductivity and fast sodium ion diffusion behavior to promote the electrochemical reaction during the charging/discharging. These results will contribute to the industrialized application of stable high-performance cathodes for sodium ion batteries. [ABSTRACT FROM AUTHOR]

Results of the complex experimental research of plasma impact on fusion reactor materials are presented. The near-wall plasma of a tokamak reactor is simulated on the linear plasma device LENTA (National Research Center Kurchatov Institute). Plasma fluence of 1022–1023 cm–2 to the material surface is provided at 1012–1013 cm–3 of plasma density in steady-state operation of the device, thus simulating the continuous regime of the fusion reactor plasma-wall conditions. The neutron effect on the first wall material (radiation damage) is also simulated by irradiation with high-energy ions accelerated by a cyclotron to MeV-range energies. The work is centered mainly on tungsten being a candidate for coating of the divertor region in the tokamak reactor. Samples irradiated at doses of 1021–1023 ion/cm2 to a high damage level from 0.1 to 80–100 displacements per atom characteristic of a durable operation of the reactor have been obtained on the cyclotron at the National Research Center Kurchatov Institute. Helium, carbon, and nitrogen ions and protons whose defect generation mechanisms are very different have been used in irradiations. Erosion data (erosion rate, erosion yield), swelling characteristics (profilometry), and microstructure changes (SEM) of the damaged surface layer are given for tungsten preirradiated with fast nitrogen ions. Proton-irradiated silicon carbide SiC has also been studied in deuterium plasma, and changes in its microstructure are found. [ABSTRACT FROM AUTHOR]

Mobile ion-enabled phenomena make β-Zn4Sb3 a promising material in terms of the re-entry phase instability behavior, mixed electronic ionic conduction, and thermoelectric performance. Here, we utilize the fast Zn2+ migration under a sawtooth waveform electric field and a dynamical growth of 3-dimensional ionic conduction network to achieve ultra-fast synthesis of β-Zn4Sb3. Moreover, the interplay between the mobile ions, electric field, and temperature field gives rise to exquisite core-shell crystalline-amorphous microstructures that self-adaptively stabilize β-Zn4Sb3. Doping Cd or Ge on the Zn site as steric hindrance further stabilizes β-Zn4Sb3 by restricting long-range Zn2+ migration and extends the operation temperature range of high thermoelectric performance. These results provide insight into the development of mixed-conduction thermoelectric materials, batteries, and other functional materials. β-Zn4Sb3 has promising thermoelectric performance, but its ionic migration properties make it prone to degradation. Here the authors exploit the ion migration in an electric field-assisted synthesis method, fast producing β-Zn4Sb3 with improved phase stability and extended temperature range for the thermoelectric operation. [ABSTRACT FROM AUTHOR]

In this study, ZnSnO3/C nanofibers are successfully prepared using a simple electrospinning method and their morphology and electrical properties are characterized. The results show that the diameter of the ZnSnO3/C nanofibers is ~190 nm and they comprise ~25 nm particles. The lithium-ion battery (LIB) fabricated using the prepared ZnSnO3/C nanofibers exhibits a high initial specific capacity of 1411.7 mAh g−1 at a current density of 0.1 A g−1. Electrospun samples maintain a good specific capacity, owing to the unique structure of the ZnSnO3/C nanofibers, which provides both buffer spaces for the large volume expansion during repeated charge-discharge cycles and fast lithium-ion transport, resulting in excellent electrochemical performance. This study provides an effective method for the preparation of ZnSnO3/C nanofibers and a potential anode material for LIBs. ZnSnO3/C nanofibers are successfully synthesized via a simple electrospinning method, which maintains a good specific capacity during the charge discharge process with a large current density. These good performances are attributed to the unique structure of the ZnSnO3/C nanofibers, which provides both buffer spaces for the large volume expansion during repeated charge discharge cycles and fast lithium ion transport. [ABSTRACT FROM AUTHOR]

In this work, we first report the facile synthesis of porous waist drum-like α-Fe2O3 nanocrystals in high yield by hydrothermal method for supercapacitor application. The as-prepared porous waist drum-like α-Fe2O3 nanocrystals have an equatorial diameter of 100–130 nm and length of 150–200 nm, which are self-assembled by numerous nanoparticles. The formation mechanism of the porous waist drum-like α-Fe2O3 nanocrystals was proposed according to a series of time-dependent experiments. The specific surface area and pore size of the porous waist drum-like α-Fe2O3 nanocrystals were measured to be 28.6 m2 g−1 and 1.7 nm, respectively. Electrochemical measurements indicate that the porous waist drum-like α-Fe2O3 nanocrystals electrode exhibits noticeable pseudocapacitive properties with a high specific capacitance up to 234 F g−1 at 2 A g−1 as well as good cycling stability and high capacitance retention of 84.6% after 2000 charge–discharge cycles. The excellent pseudocapacitive performance could be due to the unique nanostructure of the porous waist drum-like α-Fe2O3 nanocrystals, which can provide fast ion/electron transfer. [ABSTRACT FROM AUTHOR]