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In the paper, the effect of Si content on the microstructure evolution and corrosion properties of Al 0.2 CoCrFe 1.5 NiSi x (x = 0, 0.1, 0.2, 0.3) high entropy alloys (HEAs) was systematically investigated. With the addition of Si element, the microstructure changed from single face-centered cubic (FCC) phase in the Al 0.2 CoCrFe 1.5 Ni and Al 0.2 CoCrFe 1.5 NiSi 0.1 HEAs to a dual-phase structure composed of FCC and body-centered cubic (BCC) phases in the Al 0.2 CoCrFe 1.5 NiSi 0.2 and Al 0.2 CoCrFe 1.5 NiSi 0.3 HEAs. In addition, the corrosion mechanism has been analyzed by elemental analysis and corrosion morphology. The electrochemical measurement results indicated that the Al 0.2 CoCrFe 1.5 NiSi 0.1 HEA possessed the best corrosion resistance (E corr = − 215 mV Ag/AgCl , I corr = 256 nA/cm2) because the small amount of Si element improves the corrosion resistance of the single-phase FCC HEA. When the Si content increased to 4.08 at% (x = 0.2) and 6.00 at% (x = 0.3), the galvanic corrosion was caused by BCC, resulting in the selective dissolution of the BCC phase and the decrease of corrosion resistance. This research results will help to understand the potential applications of doped trace Si element as a matrix element in single-phase FCC HEAs with good corrosion resistance. • The influences of Si content on microstructure and corrosion resistance evolution of high-entropy alloy were investigated. • The corrosion mechanisms of prepared single-phase high-entropy alloy were clarified. • The effect of Si on the corrosion behavior of the high entropy alloy with of precipitates is elucidated. [ABSTRACT FROM AUTHOR]

Abstract Manipulating the stoichiometric distribution along depth direction is a promising technique to modulate the optical and optoelectronic properties of the mid-infrared sensitive lead chalcogenides at room temperature. Here, we demonstrate an optoelectronic sensitization method based on O+ beam implantation at 50 kV for polycrystalline PbSe, which can manipulate the depth profile and hence the structural properties to modulate the optical and the optoelectronic performances. Unlike the diffused material presented in previous works, the resulting material is nano-polycrystalline with average grain sizes of 17.1–29.3 nm. The optoelectronic characterizations indicate that the optoelectronic properties can indeed be modulated by the implantation dose. The responsivity up to 2.09 A/W at 4 μm has been obtained at room temperature from the sample with implantation dose of 1 × 1018 cm−2. Comparing with the diffusion counterpart, the ion prepared PbSe nanomaterial exhibits completely different structural, compositional, optical, and electrical properties. The high responsivity of this material is attributed to the high optical absorption and carrier mobility induced by O+ beam. However, the high dark current has been also observed in this material, mainly due to its low inherent potential barrier height between crystallites. Graphical abstract Image 1 Highlights • An ion beam technology for preparing mid-infrared photosensitive PbSe nanomaterial has been presented. • Enhanced optical absorption, carrier mobility and photo-responsivity have been induced by this technology. • The low potential barrier height between crystallites of this nanomaterial is caused by its small particle sizes. • The microstructure and the optoelectronic properties can be modulated by the implantation dose. [ABSTRACT FROM AUTHOR]

Abstract Nanoporous oxides of transition metals are of great potential for applications as super-capacitor electrodes because of their variable valence. However, the low conductance of electrons in oxides and slow transportation of ions in nanopores limit their performance. In this work, NiCo-contained metal/metal-oxide nanoporous composites are fabricated by one-step dealloying nanocrystallized Al 82 Ni 6 Co 3 Y 6 Cu 3 (at.%) metallic glass ribbons in KOH solutions. The capacitance of the dealloyed nanoporous composites reaches 3.35 F cm−2 (about 1522 F cm−3), which is 3–10 times higher than that dealloyed from as-spun metallic glass and crystalline precursors. The large capacitance is attributed to the combination of efficient charge transportation rate and high loading amount of active materials. These results demonstrate for the first time that the nanocrystallized metallic glasses are promising easy-processing precursors for fabricating flexible free-standing nanoporous electrodes. Graphical abstract Image 1 Highlights • Hierarchical nanoporous hybrids are fabricated by dealloying nanocrystallized metallic glass. • Optimal nanoporosity is designed by modulating the structure of metallic glasses. • Large specific capacitance is obtained. [ABSTRACT FROM AUTHOR]

In this work, flower-like SnS with N-doped carbon is synthesized by two steps including hydrothermal method and sintering at moderate temperature in a protective atmosphere. Initially, the morphology is controlled into flower-like particles in the hydrothermal method after the adding of Polyvinylpyrrolidone. The flower-like particles form a large surface area and shorten the diffusion path of ions to transfer. In addition, Polyvinylpyrrolidone is also regarded as a carbon source. After pyrolysis of Polyvinylpyrrolidone, C-N structure is easily obtained to promote the electrochemical performance in high current density. In electrochemical performance, the flower-like SnS containing N-doped carbon displays a high capacity of 1047 mAh/g after 30 th cycles and around 826 mAh/g after 50 th cycles at 100 mA/g in lithium-ion battery. Moreover, the impedance also decreases significantly. It is demonstrated that the Polyvinylpyrrolidone plays a vital role controlling the structure of SnS into flower-like powder and producing a perfect net for diffusion path. It is anticipated that SnS is a potential material for tin-based anode due to the higher conductivity and 2-Dimensional structure. Such facile method offer the functions including not only controlling the morphology and doping N-doped carbon. [ABSTRACT FROM AUTHOR]

The plasma nitriding of AISI 5140 steel was carried out assisted with hollow cathode discharge at 540 °C for 4 h under different NH 3 -N 2 mixtures. In different NH 3 -N 2 mixtures, the thickness of compound layer is different, and the phase composition, corrosion resistance and microhardness is also different. As well as, the effect of different NH 3 -N 2 mixtures on the microstructure of nitrided layer, phase composition, compound layer thickness and microhardness was characterized carefully. The results show that the thickness of compound layer, microhardness, hardening depth and corrosion resistance are related to NH 3 -N 2 mixtures. At 1:4 ratio, the thickest compound layer obtained is about 12 μm and thicker than that of the conventional compound layer (5–9 μm). At the same time, the depth of surface hardening layer is about 360 μm. The hardness value of nitrided surface is about 975 HV 0.1 , which is about 3.4 times than that (295 HV 0.1 ) of the substrate. The thickest compound layer has the best corrosion resistance characteristics. Moreover, there is no defect in the compound layer for nitrided samples. Duo to the explosion and high cost of H 2 , the use of NH 3 -N 2 mixtures greatly improve safely and reduce costs. [ABSTRACT FROM AUTHOR]

A bicontinuous nanoporous NiCoCuY metal/metal-oxide composite was fabricated by one-step de-alloying Al 85-x Ni 6 Y 6 Co 3 Cu x (x = 1, 3 and 5) metallic glasses in alkaline solutions. The electro-chemical performance of the nanoporous composites as binder-free electrodes has been evaluated. It is found that 3 at.% Cu addition can achieve the largest capacitance which is attributed to the increase in electric conductance. The capacitance of nanoporous composites can reach as high as 1.22 F cm −2 if the Al 82 Ni 6 Y 6 Co 3 Cu 3 sample was de-alloyed in 4 M KOH for 50 min. Such a one-step strategy of de-alloying metallic glass not only generates a promising functional material for energy storage, but also provides a facile way for decreasing the resistance of electrode material. [ABSTRACT FROM AUTHOR]

The increasing demand for high energy density battery systems has accelerated the development of lithium metal batteries, and it is imperative to seek strategies for alleviating the large volume change and inhibiting dendrite growth of the Li metal anode. 3D porous anode current collectors cooperated with surface modification have been considered as effective methods. Herein, we develop 3D porous Cu with modest pores by powder metallurgy method, combined with surface modification by lithiophilic Ag nanoparticles. The obtained ingenious porous structure ensures the reduction of local current density when served as the Li anode current collector, while the Ag nanoparticle layer provides numerous lithiophilic nucleation sites. Smooth and uniform Li plating morphologies are confirmed on the PM Cu@AgNP electrode surface, and the PM Cu@AgNP-Li symmetric cell presents a stable cycle of 1600 h, which effectively inhibits the Li dendrite growth. When coupled with the LiFePO 4 cathode, the assembled full cell exhibits superb capacity retention and stability for 600 cycles at 0.5 C. This facile and rational strategy with synergistic effect of modest pores and surface lithiophilicity provides a way to achieve highly stable Li metal anodes for next-generation Li batteries. • Powder metallurgy method is introduced to prepare the Li metal anode current collector. • Synergistic effect of the structure and lithiophilicity makes stable Li anode. • An average pore size of 21.2 µm is modest for the porous current collector. • Surface Ag nanoparticles significantly reduce Li nucleation overpotential. [ABSTRACT FROM AUTHOR]

High specific surface area (SSA) and optimized porous structures are necessary for supercapacitors electrodes. MOFs have porous structure which make them potential candidates for electrodes materials. Here, a MOF derivative with Ni@NiOx nanoparticles embedded in porous carbon nanosheets (Ni@NiOx/C) is prepared by hydrothermal method and carbonization process. Among them, the porous structure is tuned by the ZnO templates. Results show that the amount of doped ZnO nanoparticles can affect the morphology, porous structure and electrochemical properties of Ni@NiOx/C nanosheets electrodes. In three electrode system, the Ni@NiOx/C-2 electrode has a high specific capacitance of 752 F g−1 (at 1 A g−1) and prominent rate performance (the initial capacitance retains 56% when the current density increased to 100 A g−1). After 10,000 cycles, 99% of the initial capacitance is maintained. The assembled asymmetric device (Ni@NiOx/C-2//AC) also exhibits a high-power density (15,840 W kg−1). • The MOF derived Ni@NiOx/C materials possess tunable porous structure. • The effect of ZnO doping on the pore size distribution is analyzed in detail. • The highest specific capacitance of the electrodes is 752 F g−1. • The electrode displays excellent cyclic stability. [ABSTRACT FROM AUTHOR]

Abstract: Neodymium doped YAG transparent ceramics were fabricated by vacuum reactive sintering method using commercial α-Al2O3, Y2O3 and Nd2O3 powders as the starting materials with both tetraethyl orthosilicate (TEOS) and MgO as sintering aids. The morphologies and microstructure of the powders and Nd:YAG transparent ceramics were investigated. Fully dense Nd:YAG ceramics with average grain size of ∼10μm were obtained by vacuum sintering at 1780°C for 8h. No pores and grain-boundary phases were observed. The in-line transmittance of the ceramic was 83.8% at 1064nm. [Copyright &y& Elsevier]

Manipulating optical and electrical properties is promising for applications such as photodetectors and solar cells. Comparing with chemical preparation methods, tuning optical and optoelectronic properties by physical vapor phase methods has extra merits such as large area uniformity and CMOS compatibility. An in situ oxygen ion beam preparation method with an ion beam modulation is demonstrated for lead selenide. Polycrystalline lead selenide thin films with tunable optical band gap and low structural disorder have been fabricated using an orthogonal experimental scheme. The morphological evolution between three specific microstructures, mainly governed by ion energy and annealing temperature, has been observed. The structural characterizations indicate the presence of some oxides phases and crystallite size of hundreds of nanometers. The more suitable optical band gap within 0.75–1.1 eV was obtained at room temperature for absorption of mid-infrared photons. The ultra-low Urbach energies suggest a structurally well-ordered microstructure. The dependences of the structural, electrical and optical properties on the preparation parameters have been revealed by range analysis, indicating the main role of ion energy in the manipulations of these properties. Ion energy and beam current were revealed to be more sensitive in affecting optoelectronic properties, and the manipulation effects were demonstrated to be long wavelength sensitive. These results provide an attractive approach to manipulate and optimize the structural, electrical and optical properties of polycrystalline lead chalcogenides in mid-infrared optics and optoelectronics. Image 1 • An in-situ O+ beam preparation and modulation method for polycrystalline PbSe was demonstrated. • Three types of special microstructures were induced by interaction with ion beam. • The optical bandgap was successfully adjusted to be more suitable for detecting mid-infrared photons. • A structurally well-ordered microstructure with sharp Urbach slope was obtained. • Range analysis revealed that the ion energy plays the main role in manipulating the optical properties. [ABSTRACT FROM AUTHOR]

CdS has desirable band gap, strong light absorption, and broad application prospects in environmental treatment and energy conversion. However, CdS photogenerated carriers are easy to recombine and compromise the intended photocatalytic activity. In this study, CdS nanoparticles are prepared by a one-step hydrothermal method. The phase junction in the CdS nanoparticles is produced by controlling the hydrothermal temperature. A dynamic field is excited inside the CdS nanoparticles by the vibration of ultrasonic waves. The piezoelectric field cooperates with the phase junction to promote the separation of photogenerated electrons and holes. When the built-in electric field of the phase junction and the piezoelectric field of CdS are active independently, the separation of the carriers can be promoted. However, when the piezoelectric field cooperates with the built-in electric field of the phase junction, the separation effect of the carriers is related to the angle between the directions of the piezoelectric field and the built-in electric field of the phase junction. • A cubic-hexagonal phase junction was formed in the CdS NPs at 180 °C. • A built-in piezoelectric field was created in the CdS NPs by ultrasonic vibration. • The decolorization rate of CdS NPs was increased by the synergistic effect. [ABSTRACT FROM AUTHOR]

Transparent Er:Lu 2 O 3 ceramics were fabricated by the solid-state reaction method and vacuum sintering followed by hot isostatic pressing. The micrograph of the Er:Lu 2 O 3 transparent ceramics exhibited a pore-free structure with the average grain size of ∼2 μm. The in-line transmittance at 600 nm and 1300 nm were about 80% and 83%, respectively. The absorption, emission spectra and the decay lifetimes of Er:Lu 2 O 3 ceramics were investigated. The 3 at.% Er:Lu 2 O 3 ceramics were pumped by 967 nm InGaAs laser diodes. A maximum output power of 189 mW at 2.7 μm was obtained with a corresponding slope efficiency of 2.16%. [ABSTRACT FROM AUTHOR]

FeSe 2 shows superior advantages as anode of lithium-ion batteries (LIBs) with abundant resources, high theoretical specific capacity, and environmentally friendly. However, the FeSe 2 anode still faces great challenges balancing specific capacity, capability, and stability. In this work, we employ a self-sacrifice template of Fe-PBA coated with polydopamine to prepare FeSe 2 @Void@NC cubic nanostructures by one-step pyrolysis and selenization. The experimental results well elucidate the unique hollow cubic architectures with high surface area and abundant pore structure induce rapid adsorption storage, thus improving electrochemical kinetics. Benefiting from the enhanced ion diffusion kinetics and high conductivity through N-doped carbon coating, the FeSe 2 @Void@NC electrode demonstrates a considerable capability with a high specific capacity of 493.93 mAh g−1 (3 A g−1), and a stable cyclability with a reversible capacity of 498.5 mAh g−1 (1 A g−1) after 750 cycles. The full cells with FeSe 2 @Void@NC anode and LiFePO 4 cathode also exhibit remarkable rate capability and stable cyclability. Our research provides profound insights into the structure engineering of alternative transition metal sulfide anode for LIBs with excellent electrochemical performance. [Display omitted] • The prepared FeSe 2 @Void@NC anode demonstrates a brilliant performance as LIB anode materials. • The synergistic effect of the interface coupling and dual carbon protection greatly facilitates electron and mass transfer. • The FeSe 2 @Void@NC electrode behaves fast lithium-ion diffusion rate and favorable electrochemical kinetics. [ABSTRACT FROM AUTHOR]

Abstract: Dy3+-activated β/α′-Sr2SiO4 phosphors were successfully prepared by solid-state reaction method with ammonium chloride (NH4Cl) as the flux. The influences of calcination temperatures, amounts of NH4Cl and the concentrations of Dy3+ on phase composition, morphology and the photoluminescent properties of as-prepared powders were investigated in detail. The β and α′ phases of Sr2SiO4 were obtained with 1wt% and 2–5wt% NH4Cl, respectively, as the sintered condition was at 1000°C for 4h. With increasing the amount of NH4Cl, the morphology of phosphors changed from needlelike to regular polyhedron shape and the colors of the Sr2SiO4:Dy3+ phosphors changed from blue-green to white. The luminescence intensity of 4F9/2 → 6H15/2 transition was slightly higher than that of 4F9/2 → 6H13/2 (ΔL =2, ΔJ =2) transition owing to the low-symmetry around Dy3+ ions. The optimum concentration of Dy3+ was 2.0mol% and the concentration quenching were caused by the d–d interaction and a cross relaxation. The yellow-to-blue intensity ratio (Y/B) of Dy3+ emission did not to change with varying the Dy3+ concentration using Li+ ions for charge compensation. These indicate that this phosphor can be used as a potential candidate for the phosphor-converted white LEDs with a UV chip. [Copyright &y& Elsevier]

Abstract: Spherical monodispersed, submicron-sized Er3+:Y2O3 powders were prepared via a homogeneous precipitation method using nitrates and urea as raw materials. The structure, phase evolution and morphology of Er3+:Y2O3 precursor and the calcined powders were studied by means of XRD, TG/DTA, FTIR and SEM methods. The upconversion spectra of spherical monodispersed Er3+:Y2O3 powders were excited with 980nm laser diode (LD) and measured by a spectrofluorometer. The results showed that monodispersed spherical powders with a particle size of 200–210nm were obtained after the precipitates were calcined at 800°C for 2h. The solution concentration of Er3+ and Y3+ had a significant impact on the morphologies of the precursor and powders. Low solution concentration such as 0.015M can promote precipitation precursor to keep uniform spherical shape. The resultant monodispersed Er3+:Y2O3 phosphors exhibit upconversion luminescence properties and the intensity of the upconversion luminescence reaches the maximum when the Er3+ concentration is 3at.%. [Copyright &y& Elsevier]

In order to understand the densification kinetics of a Ti(C 0.7 N 0.3)-WC-Mo 2 C–NbC-(Co, Ni) compact, the linear shrinkages were measured using a horizontal dilatometer at different heating rates (2, 4, and 6 °C/min) in an argon atmosphere. Densification is more efficient when it is sintered at a lower heating rate. A master sintering curve was constructed over a range from the relative density of approximately 0.658–0.816; the corresponding sintering activation energy was 630 kJ/mol. With the aid of an Arrhenius curve, the sintering behaviour of cermet was analysed at different temperatures. The sintering process changed from solid-phase to liquid-phase sintering at approximately 1385 °C. The sintering activation energy turned negative when the temperature exceeded 1385 °C at a heating rate of 2 °C/min due to the formation of a liquid phase, and the exothermic process of dissolution-precipitation. • Compact densification is more efficient when sintering at lower heating rates. • A master sintering curve can be constructed for a combination of powders. • Arrhenius curve shows that the sintering of cermets is a complex process. • Sintering process changes from solid-to liquid-phase at ∼1385 °C. • Activation energy drops above 1385 °C due to liquid phase/dissolution-precipitation. [ABSTRACT FROM AUTHOR]

For achieving more functionalities of perovskite manganese oxides film, an epitaxial La 0.8 Sr 0.2 MnO 3 (LSMO) film was deposited on a flexible substrate (mica) by pulsed laser deposition. The film shows a paramagnetic-ferromagnetic (PM-FM) phase transition at 134 K together with metal-insulator transition (MIT) at 149 K. The measurement of hysteresis loop indicates that the easy-magnetization axis lied in film plane. The transport behavior can be fitted well with the small polaron model, giving out the activation energy E hop = 176.9 meV. Different from the common anisotropic magnetoresistance (AMR) in manganite film, an isotropic magnetoresistance (IMR) effect was observed in LSMO film and the relatively small thickness of LSMO film (∼ 50 nm) is a major reason for it. After the cyclic flexural bending for 1.0 × 104 times, we found the magnetic properties of LSMO film were improved. Micromagnetic detection shows that the activation energy for polaron hopping (E a = 144.7 meV) remarkably decreases by the cyclic flexural bending process. We suggested that the inhomogeneous/incompact part located at the zone of neighbouring domains become uniform and tight after circulating bending, which facilitates the rotation of domains and the polarons hopping so that the magnetic and electronic performance are enhanced. • A flexible pervoskite manganite film has been fabricated by PLD. • The film shows an exchanged polaron interactions in transport behavior. • An isotropic magnetoresistance effect was observed in film. • The magnetization and electronic transport property have been promoted after the cycling bending. [ABSTRACT FROM AUTHOR]

The composition dependent magnetic structure in epitaxial BaFe 12-x Sc x O 19 (0 ≤ x ≤ 2.1, BaScM) thin films have been investigated. Results show that with increasing Sc3+ content, the out-of-plane c -axis lattice constants of BaScM films increase but do not follow the Vegard's law. The changes in hysteresis loops indicate a variation of magneto-crystalline anisotropy from the uniaxial-type for BaFe 12 O 19 to the near-planar type for BaFe 10.2 Sc 1.8 O 19. The remanent magnetic domains change from a mixture of dots and maze-like structure to more maze-like structure as the Sc3+ content increases. The above magnetic results can be explained by a composition dependent magnetic structure transition from collinear-type ferrimagnetic magnetic structure to the non-collinear conical magnetic structure which appears at Sc3+ content x ≥ 0.6. The ZFC/FC curves further show that the conical magnetic structure transition temperature (T cone) of the films increases with the Sc3+ content until x ≥ 2.1. The above results may help better apply BaScM films in the electromagnetic devices. • With increasing Sc3+ content, lattice constant c increases but doesn't follow the Vegard's law. • With increasing Sc3+ content, magnetocrystalline anisotropy of the film changes from uniaxial-type for to conical-type. • With increasing Sc3+ content, magnetic domains change from a mixture of dots and maze structure to more maze-like structure. • The conical magnetic structure transition temperature (T cone) increases with the Sc3+ content until x ≥ 2.1. [ABSTRACT FROM AUTHOR]

Cobalt diselenide (CoSe 2) is regarded as a rising star as anode materials for sodium-ion batteries (SIBs) due to fast sodium diffusion kinetics, and high theoretic capacity. Nonetheless, the intrinsic conversion reaction mechanism inevitably causes large volume variation accompanying the insertion of sodium ion, resulting in poor cycling stability. Furthermore, its low electronic conductivity always raises unsatisfactory rate capability. In this work, we design CoSe 2 nanodots embedded in N-doped dual-carbon nanospheres (CoSe 2 /NC@NCSs) via a hard template assisted one-step selenization strategy as potential anode for SIBs. The unique hollow dual-carbon spheres as conductive matrix can provide fast electron transfer path for CoSe 2 nanodots. Meanwhile, dual-carbon spheres with inner void acts as protective barrier for confining CoSe 2 nanodots during sodiation/desodiation. Benefit from the synergetic merits of hollow dual-carbon spheres and CoSe 2 nanodots, our CoSe 2 /NC@NCSs electrode exhibits competitive electrochemical performance with a reversible capacity of 386 mAh g−1 (0.2 A g−1), and an inspiring cyclability (148 mAh g−1 at 2 A g−1) over 800 cycles. A CoSe 2 /NC@NCSs//AC device was fabricated and exhibits stable cyclability at 1 A g−1 over 450 cycles, manifesting the great potential for sodium-ion hybrid capacitors. Our work paves a new route for the electrode design strategy for SIBs. [Display omitted] • CoSe 2 nanodots confined in N-doped dual-carbon nanospheres demonstrate a brilliant sodium storage. • The synergetic effect of hollow dual-carbon spheres and CoSe 2 nanodots greatly facilitates electron and mass transfer. • The CoSe 2 /NC@NCSs electrode behaves fast sodium diffusion rate and favorable electrochemical kinetics. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) have evolved into the most potential alternatives to lithium-ion batteries (LIBs) especially for large-scale energy storage applications. However, the large radius of sodium ion inevitably causes large volume change and sluggish ion diffusion kinetics. Molybdenum disulfide (MoS 2) as a rising star of anode for SIBs has raised concern because of its high theoretical capacity. Nevertheless, MoS 2 suffers from low electronic conductivity and serious re-stacking, resulting in declined cycling stability and poor rate capability. Herein, we reported an electrostatic self-assembly process to synthesize three-dimensional (3D) crumpled MXene-bonded MoS 2 nanosheets. The MoS 2 /MXene heterostructure not only avoids the serious self-aggregation of MoS 2 nanoparticles but only maintains the chemical and mechanical stability of MoS 2 /MXene hybrids during sodiation and desodiation. Strong chemical interactions were validated on the interface of MXene and MoS 2 , favoring fast charge transfer kinetics and durable structural stability. The developed MoS 2 /MXene electrode exhibits a high specific capacity (509 mAh g−1 at 0.05 A g−1) and considerable cyclability (326 mAh g−1 at 1 A g−1 after 900 cycles), manifesting a promising application prospect for SIBs. Our work can provide a rational strategy for the electrode design strategy for SIBs. [Display omitted] • Crumpled MXene bonded MoS 2 nanosheets demonstrate a brilliant performance as SIB anode materials. • The synergistic effect of crumpled MXene and MoS 2 nanosheets, greatly facilitates electron and mass transfer. • The MoS 2 /MXene electrode behaves fast sodium diffusion rate and favorable electrochemical kinetics. [ABSTRACT FROM AUTHOR]

Abstract In the cold spraying process, previously deposited particles are hammered by the following particles, and gas temperature plays an important role in coating properties. In this study, By adding large shot peening particles to original Ti-6Al-4V (TC4) powder, five in-situ shot peening assisted cold sprayed coatings were obtained using nitrogen accelerating gas at different temperatures, and microstructure and the mechanical properties of coatings were evaluated. No phase transformation occurred during the spraying process, and the deposition efficiency was generally more than 60%. The cross-section morphology showed that the coating became denser with the increase in temperature, and the coating showed a structure of alternating dense and porous regions. Local regions struck by large shot-peening particles were denser than other regions. Therefore, the porosity, microhardness, and elastic modulus were divided into two categories. These two categories showed the same trend with temperature: The porosity decreased, whereas the microhardness and elastic modulus gradually increased. The highest values of the latter two properties were 443.4 HV 0.3 (tamped region)/390 HV 0.3 (nontamped region) and 124.8 GPa (tamped region)/110.2 GPa (nontamped region), respectively. Moreover, the bonding and shear strengths increased as the temperature increased, and the fracture morphology showed that brittle fracture was the main type of failure. In addition, by analyzing the microstructure and action depth of shot at different temperatures, it was found that the auxiliary effect of shot peening on the deformation of particles was limited at high gas temperature. Highlights • We prepared dense TC4 coating with a novel in-situ shot peening assisted cold-sprayed technology. • We focused on the local microstructure inhomogeneity and measured the porosity, microhardness and elastic modulus separately. • We modeled the mechanism to explain this special microstructure formed in in-situ shot peening assisted cold-spraying. • We found the law of the depth of shot blasting with the change of gas. [ABSTRACT FROM AUTHOR]

The magnetic properties of conical magnetic structure (CMS) hexaferrites BaFe 10.2 Sc 1.8 O 19 (BFSO) and SrFe 10.2 Sc 1.8 O 19 (SFSO) have been investigated under different magnetic fields and different temperatures. Results show that the single phase CMS hexaferrites BFSO and SFSO can be obtained as the sintering temperature exceeds 1473 K. Both the coercivity H c and remanent magnetization M r of the CMS BFSO and SFSO decrease sharply with increasing temperature below 100 K, and they become very small and almost invariant when the temperature exceeds 100 K. For both BFSO and SFSO, the field-cooling and zero-field-cooling curves differ greatly at low temperatures and resemble at high temperatures. A magnetic transition temperature T z2 from noncollinear CMS to collinear ferrimagnetic structure is observed in both BFSO and SFSO with BFSO having higher T z2 than that of SFSO. Moreover, the T z2 decreases with increasing the magnetic field in both samples generally. [ABSTRACT FROM AUTHOR]

Novel magnetically separable micro-nanostructure Ag 3 PO 4 @MgFe 2 O 4 composites were successfully prepared via an ion-exchange deposition process. With Rhodmine B (RhB) as the model organic pollutant, Ag 3 PO 4 @MgFe 2 O 4 system exhibited much superior degradation performance and stability, which was comparative to Ag 3 PO 4 and MgFe 2 O 4 system. The characterization results showed that Ag 3 PO 4 @MgFe 2 O 4 (10%) possessed high dispersion, large pore size (∼24 nm), larger transient photocurrent and longer fluorescence lifetime (∼10.83 ns). Furthermore, the effect of various parameters, such as temperature, initial pH, RhB concentration and catalyst loading on the RhB degradation were discussed in detail. Characterization results further indicate the MgFe 2 O 4 over Ag 3 PO 4 surface can inhibit Ag 3 PO 4 from photocorrosion. Comparing the activity results dependence with the characterization results, it was indicated that the dependence of the photocatalytic activity on the efficient separation of photogenerated h + -e - pairs. This result indicates that the Ag 3 PO 4 @MgFe 2 O 4 (10%) catalyst can be a promising candidate for organic dyes degradation in waste water. [ABSTRACT FROM AUTHOR]

Monodispersed and spherical β-TCP granules for 3D printing were prepared by spray drying with the surface modification of PVB. Modifier PVB attached to the particle surface to form the crosslinked network structure and keep them combine with each other into aggregates. The morphology, size, forming performance and crushing behavior of granules as well as the microstructure and density of as-fabricated β-TCP ceramics were used to optimize the PVB contents. Promising results could be expected that PVB contents were 1.0 wt.% and the average particle size of granules was 37.36 μm. The modified granules exhibited excellent forming performance with monodispersed and spherical aggregates for 3D printing. They could be completely crushed under 80 MPa without obvious inter-granules void. These granules with 1.0 wt.% PVB had defined strengths for ceramic forming. The good dispersity and flowability assured the high density and uniform porous structure of β-TCP ceramics, which were used as biological ceramic materials and completely met the standard for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Electrocatalytic water splitting is a promising route to produce hydrogen under mild conditions. Local reaction environment regulation via electrochemical activation is one of the most promising ways to achieve excellent hydrogen evolution reaction (HER) catalytic activity. Electrochemical activation technology compared with traditional synthetic technology has many advantages, such as low energy consumption, fast reaction speed, simple experimental operation, and reducing energy and environmental problems. However, the mechanism of adjusting the local reaction environment remains unclear. Here, we use a simple electrochemical activation method to control the Ni 5 P 4 particles on the nickel surface to achieve the regulation of the local reaction environment. It is found that electrochemical activation could effectively improve the catalytic activity, with hydrogen evolution overpotential of 87 mV at 10 mA cm−2. Both electrochemical measurements and theoretical calculation demonstrate the important role of in situ electrochemical activations for intermediate adsorption and desorption via nickel coordination regulation. Our strategy of adjusting the local reaction environment with nickel coordination regulation merging interfacial may create a promising pathway to developing the HER performance of metal phosphide. [Display omitted] • Electrochemical activation was used for Ni coordination regulation. • Ni with Ni 5 P 4 particles exhibits excellent HER activity. • Local reaction environment adjusting mechanism was studied. [ABSTRACT FROM AUTHOR]

Tuning the optical and optoelectronic properties of materials is attractive for solar energy and infrared sensing applications. Here, we proposed an ion beam co-growth preparation method that can continuously tune the optical band gap and absorption and thus optoelectronic properties of lead selenide. The optical band gap of the material can be effectively tuned by ion energy and beam current, varying continuously from 0.79 to 1.03 eV. The tuning mechanism of ion beam on optical and optoelectronic properties was revealed by orthogonal range analysis. The results of range analysis on optical properties show that ion energy and beam current play the key role in adjusting the optical band gap and absorptivity. Ion beam regulation also reduces the Urbach energy of the material, suggesting low thermal disorder and structural defects of the resulting material. The photoresponsivity and specific detectivity of thin film devices can also be effectively tuned by the ion energy and beam current. The material is sensitive to mid-infrared radiation, and the preliminary photoresponsivity is up to 0.61 A/W at 3 µm, which is better than those of traditional thermal diffusion in oxygen atmosphere. [Display omitted] • An ion beam co-growth preparation was demonstrated for tuning optical and optoelectronic properties. • Tunable optical bandgap was induced by low energy ion beam from 0.79 to 1.03 eV. • The resulting material is IR photo-sensitive with responsivity up to 0.61 A/W at 3 µm. • The Tuning mechanisms of low energy ion beam on optical and optoelectronic properties were revealed. [ABSTRACT FROM AUTHOR]

Tuning the optical and optoelectronic properties of materials is attractive for solar energy and infrared sensing applications. Here, we proposed an ion beam co-growth preparation method that can continuously tune the optical band gap and absorption and thus optoelectronic properties of lead selenide. The optical band gap of the material can be effectively tuned by ion energy and beam current, varying continuously from 0.79 to 1.03 eV. The tuning mechanism of ion beam on optical and optoelectronic properties was revealed by orthogonal range analysis. The results of range analysis on optical properties show that ion energy and beam current play the key role in adjusting the optical band gap and absorptivity. Ion beam regulation also reduces the Urbach energy of the material, suggesting low thermal disorder and structural defects of the resulting material. The photoresponsivity and specific detectivity of thin film devices can also be effectively tuned by the ion energy and beam current. The material is sensitive to mid-infrared radiation, and the preliminary photoresponsivity is up to 0.61 A/W at 3 µm, which is better than those of traditional thermal diffusion in oxygen atmosphere. [Display omitted] • An ion beam co-growth preparation was demonstrated for tuning optical and optoelectronic properties. • Tunable optical bandgap was induced by low energy ion beam from 0.79 to 1.03 eV. • The resulting material is IR photo-sensitive with responsivity up to 0.61 A/W at 3 µm. • The Tuning mechanisms of low energy ion beam on optical and optoelectronic properties were revealed. [ABSTRACT FROM AUTHOR]

Nanofibers are widely used in electrochemical energy storage and conversion because of their large specific surface area, high porosity, and excellent mass transfer capability. Electrospinning technology stands out among the methods for nanofibers preparation due to its advantages including high controllability, simple operation, low cost, and wide adjustability. The practical performance of these fibers is largely determined by their structure. Thus, the development of functional nanofibers must start with the regulation of their structure which has been demonstrated as an effective approach to optimize the electrochemical performance of fiber-based electrodes. After a brief introduction of the principles for electrospinning, the dependence of the fibers' structure on the electrospinning parameters is discussed, providing reliable guidance for the controlled modulation of fiber-based architectures. To highlight the advantages of controllability, the structures of the as-spun fibers are regulated at different scales, including the pores within the fibers, the morphology of the fibers, and the assembly manner of the fibers. Then, the use of these fibers for electrochemical energy storage and conversion is discussed with focused attention on the structure-performance relationship. The current challenges facing the electrospinning technology and proposed prospects for this emerging field are summarized to conclude this review. [Display omitted] [ABSTRACT FROM AUTHOR]

Transparent chromium doped Y 3 Al 5 O 12 ceramics with excellent optical qualities were successfully fabricated by solid state reaction sintering using divalent dopants (CaO and MgO) as sintering aids, and the conversion efficiency of Cr 4+ ion in Cr: YAG ceramic was effectively regulated by various approaches. All samples were fully transparent after vacuum sintered at 1820 °C for 8 h. It was found that under fixed amount of divalent dopants, the conversion efficiency of Cr 4+ ion in Cr: YAG ceramics was significantly increased by increasing Cr doping concentration, elevating annealing temperature, prolonging annealing soaking time or adopting oxygen annealing atmosphere. The absorption coefficient of as fabricated 0.1 at.% Cr: YAG ceramics at 1030 nm reached up to 5.2 cm −1 after annealed at 1300 °C for 30 h under an oxygen atmosphere. It was much higher than that of corresponding single crystal fabricated by traditional Czochralski method. [ABSTRACT FROM AUTHOR]

The advanced efficiency of metallic glasses in degrading organic water pollutants has attracted wide interests. Yet the decolorization efficiency decreases in alkaline solutions which remains a challenge for their application. In this work, the performance of Al 91-x Ni 9 Y x (x = 0, 3, 6, 9 at.%) metallic ribbons in degrading azo dye in aqueous solutions at wide pH conditions is studied. It is surprising to find that the reaction activity of Al-based metallic glass in alkaline and acidic azo dye solution is about 1.5 and 189 times higher than that in neutral solutions, respectively. The low reaction activation energy and formation of nano-porosity on the surface of metallic glass are responsible for the high reactivity in alkaline and acidic solutions. The reaction activity can be further enhanced by modifying the alloy composition. These findings suggest that the Al-based metallic glasses hold promising potential in degrading azo dyes solutions, especially in alkaline and acidic environments. [ABSTRACT FROM AUTHOR]

SeS 2 possesses the combined merits of S and Se with considerable capacity and high electronic conductivity, but is still hindered by a shuttle effect of lithium polysulfides/polyselenides and sluggish conversion kinetics. Herein, high–efficiency heterogeneous Ni 2 P/CoP catalysts implanted into MOF–derived carbon arrays (Ni 2 P/CoP@NC) are developed to simultaneous immobilize polysulfides/polyselenides and regulate their conversion. The Ni 2 P/CoP catalysts with hollow and hierarchical structures extremely expose abundant catalytic and adsorption sites for LiPS/LiPSe conversion reaction. Meanwhile, the strong chemical binding of Ni 2 P/CoP towards LiPSs/LiPSes through Ni–S, Ni–Se, Co–S and Li–P bonds favors for the regulation of polysulfide/polyselenide conversion. The DFT calculation results corroborate the heterogeneous Ni 2 P/CoP interface provides depressed lithium–ion diffusion barriers to promote the polysulfide/polyselenide conversion kinetics. Benefiting from abundant catalytic and adsorption sites, strong chemical binding towards LiPSs/LiPSes and depressed lithium–ion diffusion barriers, the Ni 2 P/CoP@NC catalysts enable considerable specific capacities, superior rate performance and stable cycling performance for Li–SeS 2 batteries. [Display omitted] • Hollow heterogeneous Ni 2 P/CoP nanoparticles implanted in carbon arrays are developed for SeS 2 immobilizers. • Ni 2 P/CoP heterostructures chemically immobilize LiPSs/LiPSes through Ni-S, Ni-Se, Co-S and Li-P bonds. • A reduced diffusion barrier of Li 2 S on Ni 2 P/CoP enables efficient catalytic conversion. • SeS 2 @Ni 2 P/CoP@NC cathode exhibits superior rate performance and stable cycling performance. [ABSTRACT FROM AUTHOR]

The magnetic properties of Sr 3-x Ba x Co 2 Fe 24 O 41 (0 ≤ x ≤ 3) Z-type hexaferrite powders have been investigated from 5 to 390 K. Results show that the lattice parameters ( a and c ) of the hexaferrite change with the Ba 2+ /Sr 2+ ratio but don't follow the Vegard's law. The magnetization reversal process changes from three-stage reversal process to two-stage reversal process as the Ba 2+ /Sr 2+ ratio increases. The above composition dependent magnetization reversal process of Sr 3-x Ba x Co 2 Fe 24 O 41 can be explained with the composition dependent conical magnetic structure model. The saturation magnetization of Sr 3-x Ba x Co 2 Fe 24 O 41 decreases only slightly with increasing the Ba content, but rapidly with increasing temperature. The coercivity (H c ) decreases with increasing temperature generally. Increasing Ba 2+ /Sr 2+ ratio leads to an increase in H c firstly and then H c decreases again at temperatures below 250 K. An increase in temperature does not lead to enormous changes of the magnetization in the field cooling curves below 390 K, but leads to a successive increase of the magnetization in the zero field cooling curves generally. [ABSTRACT FROM AUTHOR]

A novel Sr 3 Ti 2 O 7 :Eu 3+ red phosphor with double-layered perovskite structure was successfully synthesized by solid-state reaction method using Li + ions as charge compensators. Its crystal structure, morphology and photoluminescence under different calcination temperatures and different compensation styles of Li + were investigated. The phosphor could obtain pure tetragonal perovskite phase with I4/ mmm space group at 1300 °C. Non-stoichiometric (NSC) compensation could keep more Sr 2+ ions to hold the perovskite structure stable for higher doping concentration of Eu 3+ . The emission was dominated by the electric-dipole transition with obvious peak splitting due to two different doping sites with lower symmetry of Sr 2+ . Layered structure provided bigger space to hold more Li + ions and NSC style had bigger advantage on the luminescence enhancement for higher doping concentration. Better excitation matches, higher quantum yield (25.1%, λ ex = 395 nm) and better color rendering properties provided a potential red material for white LEDs. [ABSTRACT FROM AUTHOR]

Series of Eu 3+ substituted Na(Gd 1− x Eu x )MgWO 6 phosphors were successfully synthesized by a EDTA-citric acid complexing method. The crystal structure, doping site, morphology, and luminescent properties under different Eu 3+ concentrations were investigated by XRD, Rietveld refinement, Raman spectra, FTIR, SEM and fluorescence spectra as well as Judd–Ofelt analysis and quenching theory. The phosphors had monoclinic double perovskite structure with space group C2/m , rock-salt ordering of B-site (Mg/W) and layered ordering of A-site (Na/Gd/Eu). The redshift of Raman T 2g (1) mode proved Eu 3+ ions had uniformly substituted into A-site. The rare alternative excitation appeared in phosphors that the charge transfer band (CTB) altered from O–W into O–Eu and the strongest excitation altered from CTB into f – f transition of Eu 3+ . The quenching concentration for hypersensitive 5 D 0 – 7 F 2 transition of Eu 3+ reached up to 50.0 mol%, while both the intensity ratio of 5 D 0 – 7 F 2 / 5 D 0 – 7 F 1 and Judd–Ofelt parameter Ω 2 reached the maximum. These two channels of alternative excitation and delayed concentration quenching dually enhanced the luminescence of NaGdMgWO 6 :Eu 3+ phosphor. It is a potential red material for NUV and blue LED chips. [ABSTRACT FROM AUTHOR]

Solid content of suspension for spray drying was systematically investigated to obtain spherical and dense Nd: granulated particles. The rheological behavior, morphology, size and distribution, apparent and tap densities, and transmittance measurements were used as tools to guide the selection of solid content of suspension. The balanced solid content were 42.0 wt.%. The granulated particles exhibited close to mono-dispersed, spherical and uniform dense aggregates, and mean size was ∼35 μm. Under 60 MPa pressure, the granules were completely crushed without obvious inter-granules void. The homogeneous element distribution and fine microstructure provided high optical quality of Nd:YAG ceramics and the transmittance at 1064 nm reached up to 84.90%. [ABSTRACT FROM AUTHOR]

Highlights: [•] ZnO micro-/nanostructures were synthesized by combined microwave-ultrasonic wave method. [•] Morphologies of ZnO micro-/nanostructures could be modulated by varying reaction conditions. [•] HEPES plays a crucial role in the controllable synthesis of ZnO micro-/nanostructures. [•] ZnO micro-/nanostructures exhibit shape-dependent photocatalytic activity. [•] Spindle-like ZnO microstructures show superior photocatalytic activity. [Copyright &y& Elsevier]

• Low-cost flexible transparent conductive oxide (TCO) film. • Low-cost, indium-free and flexible perovskite CaVO 3 TCO films grown on mica substrates. • Superior stable optical transparency and electrical conductivity after 105 bending cycles. Transparent conducting oxides (TCOs), such as indium-tin oxide (ITO) and indium gallium zinc oxide (IGZO), are essential components in the design of flexible optoelectronic devices. However, it is still a challenge to prepare low-cost flexible transparent conductive film for achieving the flexible functionality together with high optical transparency and electrical conductivity. Herein, fluorphlogopite (mica) is selected as the bendable and transparent substrate for the fabrication of low-cost perovskite CaVO 3 TCO epitaxial film. Benefitting from thin mica substrate with high Young's modulus of 200 GPa, flexible CaVO 3 TCO epitaxial film exhibits high mechanical stability in terms of electrical conductivity and optical transparency after bending up to 105 cycles. The change of resistance can reflect the bending curvature and strain state. Our results provide a new pathway to design superior mechanical flexibility and stability CaVO 3 TCO films for application in flexible, light-weight, and portable smart optoelectronic devices. [ABSTRACT FROM AUTHOR]

Abstract: Double perovskite (Sr0.98− m Ba m Eu0.02)2Ca(Mo1− n W n )O6 phosphors were successfully synthesized by an improved citrate–EDTA complexing method. The structure evolution and the resulting luminescence variation were systematically investigated by X-ray diffraction with Rietveld structure refinement, Fourier transform infrared spectra, Raman spectra, diffuse reflection spectra and photoluminescence spectra. The increased crystal symmetry and increased lattice parameters were observed from (Sr0.98− m Ba m Eu0.02)2CaMoO6 phosphors. These series of phosphors could be effectively excited by near ultraviolet light and emitted a dominant 594nm (5D0–7F1). The hypersensitive 5D0–7F2 transition (615nm) varied with the changed structure symmetry. The CIE chromaticity coordinates were tuned from (0.642, 0.348) to (0.601, 0.389). The luminescence intensity of W6+ substituted powders was greatly enhanced by the blue shift of charge transition band of (Mo/W)O6 with stable emission color. The composition-optimized Sr2Ca(Mo0.5W0.5)O6:Eu phosphor had the highest luminescence intensity and quantum yield comparing to the commercial red phosphors. [Copyright &y& Elsevier]

Abstract: Monoclinic bismuth vanadate (m-BiVO4) micro-/nanostructures with different sizes and morphologies were successfully prepared via a facile and rapid microwave and ultrasonic wave combined technique. The obtained BiVO4 products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM) and UV–vis diffuse reflection spectroscopy (DRS). It was found that the solvent and pH value had a significant influence on morphology, size and crystalline structure of the product. Nut-like, potato-like and broccoli-like monoclinic BiVO4 were fabricated in different solvents. The crystal phase could be modulated by varying the pH value of reaction system. The photocatalytic activities of the products were also evaluated by the degradation of Rhodamine B (RhB) under visible light irradiation. The result revealed that the photocatalytic activities of BiVO4 nanostructures were closely related to the crystalline phase, band gap and particle size. Monoclinic BiVO4 nanoparticles with small crystal size and large band gap exhibited remarkable photocatalytic performance. [Copyright &y& Elsevier]