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Thermal insulating coatings effectively reduce heat loss, helping to save energy and reduce emissions. However, their thermal insulation performance decreases notably as temperature rises due to a single inhibition for heat transfer. Additionally, they have limited high-temperature resistance. To overcome these challenges. We developed a composite thermal insulation coating (CTIC). It was prepared through simple physical blending and can be effectively combined with various substrates. It achieves effective suppression of heat conduction and heat radiation, demonstrating excellent thermal insulation capabilities owing to the synergistic effect of fumed silica, Al 2 O 3 , and MnO 2. It exhibited a low thermal conductivity of 0.0843 W/(m·K) at 500 °C. The 10 mm CTIC decreased the high temperature from 1008.9 °C to 339.5 °C. Moreover, the CTIC could withstand temperatures of up to 1200 °C. This work offers fresh insights into the design of thermal insulating coatings. • Al 2 O 3 and MnO 2 can enhance radiation thermal insulation. • Fumed silica significantly inhibits both solid and gaseous thermal conduction • Simultaneously inhibiting heat conduction and heat radiation can significantly improve thermal insulation performance in high-temperature environments. [ABSTRACT FROM AUTHOR]

Abstract Self-assembled nano-honeycomb WS 2 modified by graphene doping were prepared by improved one step hydrothermal method. In this hybrid structure, graphene plays a key role of transferring the morphology from the nanowire microporous spheres to graphene-supported nano-honeycomb plane structure, which has the larger the specific surface area and higher conductivity. This anode delivers the superb electrochemical performances of lithium/sodium ion batteries with high specific charge capacity (953.1/522.3 mAh·g−1 at 0.1 A·g−1), long cycling life (more than 350/200 cycles at 1 A·g−1), and high charge/discharge rates (up to 10/5 A·g−1). This nano-honeycomb structure WS 2 composite anode with facile hydrothermal process, as well as superb electrochemical performances, makes it attractive for the potential applications in lithium/sodium ion batteries. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

To achieve significant reduction of dielectric loss and enhancement of dielectric tunability for actual applications, a Ba 0.51 Sr 0.34 TiO 3 film modified by Y/Mn alternate doping (Y/Mn-BST 0.85 ) is prepared by an improved sol-gel method, where the film is composed of 12 layers, and odd number layers are preheated. For comparison, BST 0.85 , Y-BST 0.85 and Mn-BST 0.85 films are also prepared. XRD shows four films are ABO 3 cubic perovskite structures. The BST 0.85 film shows the smallest lattice parameter and donor doping because rich Ti 4+ ions enter into A sites to replace some Sr 2+ and Ba 2+ ions. Besides the donor doping, three doped BST 0.85 films exhibit slightly larger lattice parameters and acceptor doping because Y 3+ or Mn 2+ ions replace some Ti 4+ ions at A sites. The Y/Mn-BST 0.85 film shows the largest lattice parameter and the strongest crystallinity because Y-BST 0.85 layer and Mn-BST 0.85 layer match well in lattice structure. Compared to stoichiometric films, four nonstoichiometric films show markedly decreased dielectric losses. The Y/Mn-BST 0.85 film exhibits the lowest dielectric loss with 0.45 ~ 0.54% under the conditions of − 40 to 40V and 100 kHz, and 0.43 ~ 2.29% under the conditions of 10 Hz ~ 1 GHz and 0 V, thus can satisfy actual applications including tunable microwave application at high frequencies. The related mechanisms are studied by measuring leakage current density, observing AFM and analyzing XPS besides analyzing the XRD patterns. [ABSTRACT FROM AUTHOR]

Si nanoparticle (Si-NP) composite anode with high rate and long cycle life is an attractive anode material for lithium-ion battery (LIB) in hybrid electric vehicle (HEV)/pure electric vehicle (PEV). In this work, a carbon nanotube (CNT)/reduced graphene oxide (rGO)/Si nanoparticle composite with alternated structure as Li-ion battery anode is prepared. In this structure, rGO completely wraps the entire Si/CNT networks by different layers and CNT networks provide fast electron transport pathways with reduced solid-state diffusion, so that the stable solid-electrolyte interphase layer can form on the whole surface of the matrix instead of on single Si nanoparticle, which ensure the high cycle stability to achieve the excellent cycle performance. As a result, the CNT/rGO/Si-NP anode exhibits high performances with long cycle life (≈455 mAh g−1 at 15 A g−1 after 2000 cycles), high specific charge capacity (≈2250 mAh g−1 at 0.2 A g−1, ≈650 mAh g−1 at 15 A g−1), and fast charge/discharge rates (up to 16 A g−1). This nanostructure anode with facile and low-cost synthesis method, as well as excellent electrochemical performances, makes it attractive for the long life cycles at high rate of the next generation LIB applications in HEV/PEV. [ABSTRACT FROM AUTHOR]

Abstract: Mn and Y alternately doped Ba0.6Sr0.4TiO3 (Mn/YBST) films were prepared by improved sol–gel method on Pt/Ti/SiO2/Si substrates. The effect of different doped concentrations (0.5%, 1.0%, 1.5%, 2.0% and 2.5%) on crystallization and dielectric properties of BST films was studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and HP4294A. All films grow along (110) orientation, possessed dense nodular microstructure, exhibited decreased grain size and improved morphologies with smaller average roughness. As a result, the doping behavior changes from donor doping to acceptor doping and again to donor doping and the dielectric constants and the dielectric losses tend to decrease with increasing doped concentration. 1.5% corresponds to the optimized dielectric properties with the dielectric losses of about 0.007 and the figure of merit (FOM) of 38.83 at 100kHz. Also, the related mechanisms and the dielectric properties at microwave frequencies are discussed. [Copyright &y& Elsevier]

Smooth and dense preheated cerium (Ce) and manganese (Mn) codoped barium strontium titanate (CeMn-BST) films with various thicknesses have been prepared by improved sol-gel method. Capacitance-voltage curves show that with increasing film thickness, combination of dielectric properties are significantly improved with optimized values of about 1300 moderate permittivity, less than 0.007 dielectric loss, more than 58% tunability and hence near 180 figure of merit (FOM) for eight-layer CeMn-BST film. The objective of this paper is to study the improved mechanisms for such excellent dielectric properties. XRD shows that the films layered-grow mainly along (110) orientation and exhibit ABO3cubic perovskite structure. As film thickness increases, Ce3+and/or Mn2+ions are showing doping modes from donor doping to acceptor doping, the crystallization of films is enhancing, but the average grain sizes of the films show gradually decreased trend from about 45nm to 25nm in terms of the intensities of (110) diffraction peaks. AFM indicates that the films are getting smoother with smaller roughness with increasing thickness. XPS reveals that the films reveal decreased non-perovskite structure, element core levels and Fermi levels with increasing thickness. Leakage current densities are significantly decreased almost at two orders of magnitude with increasing thickness. Pure BST films are compared. [ABSTRACT FROM AUTHOR]

By adjusting film thickness, smooth and dense Mn and Y alternately doped Ba0.6Sr0.4TiO3(Mn/Y-BST) films have been designed and prepared by improved sol-gel method, and the structure and dielectric properties of the films have been studied. X-ray diffraction (XRD) reveals that all films grow along (110) orientation, doped Mn2+ions or Y3+ions show acceptor doping, and thicker film shows stronger crystallization. Atomic force microscope (AFM) shows the films are relatively smooth without obvious cracks or pinholes. Scanning electronic microscope (SEM) indicates that from substrate to surface the films show nodular microstructures to columnar ones without obvious interface among nodular microstructure layers. Compared to pure BST film or Mn or Y doped BST films, all alternately doped films show markedly improved structures and dielectric properties, which is strongly dependent on film thickness. 6-layer Mn/Y-BST film shows best structure and combination of dielectric properties with dielectric loss of 1.18%, tunability of 38% and figure of merit (FOM) of 32.2 at 100 kHz. [ABSTRACT FROM AUTHOR]

Manganese (Mn) and yttrium (Y) alternately doped Ba0.6Sr0.4TiO3(BST) films are novelly designed as MnBST/YBST/MnBST/YBST and prepared layer-after-layer on Pt wafer electrodes, and two films where one with the first layer preheated (1Mn/YBST) and the other with four layers preheated (4Mn/YBST) are focused on. XRD shows that two films grow along (110) orientation and reveal ABO3cubic perovskite structures and donor doping, but 4Mn/YBST film shows larger average grain size. SEM demonstrates that 1Mn/YBST film is composed of one 630nm-thick layer with nodular microstructure and the other 570nm-thick surface layer with columnar microstructure, whereas 4Mn/YBST film is 670 nm thick with nodular microstructure. AFM shows that two films are smooth with no cracks, but 4Mn/YBST film is denser with smaller roughness. Two films show more than 55% high tunabilities, but 4Mn/YBST film also reveals low losses of 0.0062∼0.0156 and high figure of merit (FOM) of near 90 at -35V and 100 kHz, fully meeting the needs of tunable microwave applications. [ABSTRACT FROM AUTHOR]

Cerium (Ce) and manganese (Mn) codoped Ba0.6Sr0.4TiO3(BST) films were prepared by improved sol-gel method and the effect of preheating on their dielectric properties was investigated. X-ray diffraction (XRD) reveals that the films grow principally along (110) orientations and show cubic perovskite structures. Preheating corresponds to smaller FWHMs, stronger crystallization and larger grain sizes, and preheating with codoping corresponds to the smallest FWHM, the strongest crystallization and the largest grain size. The prepared film can show tunability of 55.7%, dielectric loss of 0.0074∼0.0175 and approximately 75 FOM, meeting the needs of tunable microwave applications. [ABSTRACT FROM AUTHOR]

Abstract: Mn and Y alternately doped Ba0.6Sr0.4TiO3 film, denoted as Mn/Y-BST film, has been designed and prepared by improved sol–gel method, and the structure and dielectric properties of the film have been studied. Y or Mn doped BST film is also studied. X-ray diffraction reveals that all films grow along (110) orientation and show polycrystalline cubic perovskite structures, and Y3+ and Mn2+ ions enter into B-sites of ABO3 perovskite structure and substitute Ti4+ ions. The Mn/Y-BST film reveals better crystallization with larger crystal grain size. Atomic force microscopy and scanning electron microscopy confirm that the Mn/Y-BST film exhibits better crystallization. X-ray photoelectron spectroscopy shows that the Mn/Y-BST film presents less surface non-perovskite structure. Accordingly, the Mn/Y-BST film exhibits significantly nonlinear improvement in combination of dielectric properties. These results indicate that Mn/Y alternate doping is a novel route to excellent BST films for tunable microwave applications. [Copyright &y& Elsevier]

Abstract: Cerium and manganese codoped Ba0.6Sr0.4TiO3 (CeMn-BST) film and pure BST, Ce-BST and Mn-BST films were prepared. Influence of preheating on film crystallization and growing behavior was studied. X-ray diffraction (XRD) reveals that all films mainly grow along (110) orientation and show cubic ABO3 perovskite structures, and the preheating promotes Ce3+ and Mn4+ ions enter into B-sites and substitute Ti4+ ions. Preheating enhances crystallization and causes the strongest crystallization with CeMn-codoping. Atomic force microscopy (AFM) exhibits that films preheated show layered growth, while those not preheated show island growth, which are related to layer number and doping. Therefore, the films preheated show larger permittivities, higher tunabilities, and lower dielectric losses except the pure BST film and higher figures of merit (FOMs). Preheating with CeMn-codoping causes best dielectric properties with 56% tunability, 0.0037–0.0091 loss and near 150 FOM, meeting the needs of tunable microwave applications. [Copyright &y& Elsevier]

The structural integrity and continuity are prerequisites for exploiting the performance advantages of aerogels, while limitations in mechanical properties, such as low strength, high brittleness, and poor processability confine fully intact aerogels to laboratory settings. Here, a composite aerogel SPCCAM designed with hierarchical structuring into 1D building blocks at the nanoscale and honeycomb‐like anisotropic architecture at the microscale is presented. The inner carboxylated cellulose nanofiber core (CNFs‐C) exhibits much higher strength than the intermediate polybenzoxazine (PBOZ) shell, and the interface is highly reinforced by a crosslinked network of amino and hydrogen bonds, forming a highly stable 1D building block. Superhydrophobic SiO2 nanoparticle (hydrophobic‐260) is discretely distributed on the outer surface of the PBOZ shell, resulting in a nanoscale lotus leaf effect. Thus, the SPCCAM demonstrates outstanding properties including ultrahigh strength, excellent deformability and fatigue resistance, good machinability, ultralow thermal conductivity and coefficient of linear expansion, and superhydrophobicity from the inside out and long‐term hydrophobic stability along the radial direction of microscale channels, defining a novel method for designing aerogels with superior integrated mechanical, thermal insulation, and hydrophobic properties, and offering an attractive solution for high‐efficiency thermal insulators in high‐moisture extreme environments, such as deep‐sea and polar regions. [ABSTRACT FROM AUTHOR]

Carbonaceous materials show more and more obvious applications in potassium (K) ion battery (KIB) and sodium (Na) ion battery (NaIB) because K and Na have higher reserves than lithium (Li). However, the rate performance and cycle stability of KIBs and NaIBs are still hindered by huge volume change during ions insertion-extraction process and poor kinetics caused by larger volume of K+ and Na+ ions. Compared to graphite and hard carbon, nitrogen (N)-doped porous carbonaceous materials may provide good interfacial wettability and numerous ion transport channels, but low first coulombic efficiency is detrimental to the application of full-battery. Here, N-doped porous carbon (NPC) with a providential specific surface area is synthesized by a facile and activation-free way. Benefiting from N-doping and porous structure, KIBs and NaIBs display an enhanced rate capacity and cycle performance. The storage mechanism and kinetic characteristics of K and Na ion during charge and discharge are also discussed. Comprehensive performance indicates that NPC can obtain a better improvement in surface-driven KIBs than intercalation dominated NaIBs, and can provide some new design concepts for practical applications. [ABSTRACT FROM AUTHOR]

The inherent low ionic conductivity of PVDF‐based electrolytes at room temperature and lithium dendrite penetration hinder its further application. Herein, a LaF3 doped Poly(vinylidene fluoride‐chlorotrifluoroethylene) (P(VDF‐ctfe)) quasi‐solid electrolyte is developed. High‐flux channels are created due to the optimization of the lithium environment that lanthanum preferentially competes coordination with anionic species for relaxing lithium hopping. Lithium carriers are therefore highly free and unbound at the molecular level, resulting in a high ionic conductivity (σ) of 0.7 mS cm−1 and a transfer number (tLi+) of 0.79 at 25 °C. Moreover, the in situ organic–inorganic LiF‐rich dielectric layer effectively improves the stability and compatibility of the electrode/electrolyte interface, ensuring interfacial lithium conduction while facilitating stable Li+ plating/stripping. As a result, the optimized Li/ATCSE‐3%/Li can deliver favorable compatibility at 0.1 and 0.3 mA cm−2 for stable Li+ plating/stripping for 2000 and 1200 h, respectively. The high‐mass loading (6.4 mg cm−2) pouch cell delivers a stable cycling performance over 100 cycles with a capacity retention of 85.8% at 0.3 °C. This work is anticipated to provide considerable insight into the creative design of lithium transport of polymer‐based for practical quasi‐solid‐state lithium metal batteries. [ABSTRACT FROM AUTHOR]

A hybrid aerogel structure for hydrogen sensing was produced and tested, which consists of Pd nanoparticles decorated on a TiO 2 aerogel skeleton structure with large specific surface areas and high porosity. The effects of decorated with different contents of Pd nanoparticles on the microstructure of anatase TiO 2 aerogel and the hydrogen response characteristics were investigated. The contribution of the doping of Pd nanoparticles to the specific selectivity of the anatase phase TiO 2 aerogel for hydrogen sensing was investigated. Benefiting from highly interconnected porous networks of aerogel, ultra-large specific surface area, and homogeneous Pd nanoparticles dispersion, the resulting Pd nanoparticle-decorated TiO 2 3D hybrid aerogel hydrogen sensors express high hydrogen sensing performance. The response was 4.8 toward 100 ppm hydrogen at the optimal working temperature of 325 °C, with a short response time (<2 s), short recovery time (<22 s), and high selectivity and long-term stability. A hydrogen-sensitive mechanism is proposed in which metal atom doping causes more oxygen defects in metal oxide semiconductor lattice. The approach of constructing aerogel network structures by decorating metal nanoparticles on metal oxide semiconductors provides a new way to develop gas sensors. • Pd nanoparticles-decorated TiO 2 aerogel structure was prepared by sol-gel method and supercritical drying method for hydrogen sensing. • Very large specific surface areas and highly interconnected porous networks. • Short response time(<2s) and recovery time(<22s) of anatase Pd-modified TiO 2 aerogel structure for hydrogen sensing. • High selectivity of Pd nanoparticles-decorated anatase phase TiO 2 aerogel structure for hydrogen sensing. [ABSTRACT FROM AUTHOR]

SiO 2 aerogel is a promising lightweight and high-efficiency thermal insulation material for applications in construction, industrial, aerospace vehicles, etc., but weak mechanical properties limit its further development and application. In order to overcome this challenge, we combined the design concepts of elastic group's introduction and structural strengthening of cellulose nanofibers with a directed freezing process, and successfully realized an anisotropic and high-strength SiO 2 /cellulose nanofiber composite aerogel. Under the low density of 0.247 g/cm3, the maximum compression strength of the aerogel in the radial direction is as high as 18.08 MPa, corresponding to a high fracture strain of 75.67%, and it also exhibits an excellent fatigue resistance, with only a slight plastic deformation of 6.5% after 100 load-unload cycles at a high compression strain of 50%. In addition, the aerogel exhibits an ultra-low thermal conductivity (0.01714W/(m·K)) in the radial direction, and also has a superhydrophobicity (water contact angle 150.8°) and a long-term hydrophobic stability (saturated mass moisture absorption rate 0.44%). The combination of these properties makes it an ideal material for thermal superinsulation in environments where both integrated mechanical properties and hydrophobic properties are critical. [ABSTRACT FROM AUTHOR]

[Display omitted] In order to fundamentally suppress the shuttle effect, N 2 Plasma & Al 2 O 3 magnetron sputtered separators (Al 2 O 3 @ N -PP) are proposed for lithium-sulfur batteries (LSBs). Such a dual-functional polysulfides (LiPSs) barrier separator greatly inhibits the shuttle effect from the perspective of physical and chemical interaction. Physically, the inherently electronegative amorphous Al 2 O 3 first achieves the repulsion of LiPSs to the sulfur cathode through the electrostatic repulsive effect, effectively preventing a large amount of soluble LiPSs from accumulating at the separator. At the same time, the Al 2 O 3 film seals the shuttle channel of LiPSs to a certain extent. Chemically, N 2 plasma-doped N heteroatoms form a lithium bond with Li+ in LiPSs to achieve the first step chemical adsorption and anchoring of LiPSs. When the LiPSs reaches the amorphous Al 2 O 3 film, more stable chemical bonds are formed between Al3+ and S2−, Li+ and O2– to achieve more effective adsorption and anchoring of LiPSs. At 1C with a high sulfur loading up to 3–5 mg cm−2 the LSB contributes a specific charge capacity of 717.4 mAh g−1, with high retention rate up to 75.49 % after 450 cycles. The U-shaped electrolytic cell experiment and ultraviolet–visible spectrum experiment confirmed the LiPSs barrier function of the functional separator. [ABSTRACT FROM AUTHOR]

Lithium-sulfur battery (LSB) is considered a kind of potential energy storage systems on account of its high theoretical capacity (1675 mAh·g−1) and energy density (2500 Wh·Kg−1). However, poor ionic/electronic conductivity and annoying shuttle effects still need to be resolved. Here a highly flexible and highly conductive MXene (Ti 3 C 2 T x) interlayer with a sandwich structure is reported, the surface of which is a TiS 2 /TiO 2 heterostructure formed by vulcanized. In this framework, the role of TiO 2 nanoparticles is adsorbent to combine the lithium polysulfides (LiPSs), and the TiS 2 nanoparticles function as catalysts to further facilitate the conversion of long-chain LiPSs to short-chain Li 2 S 2 /Li 2 S under the high conductivity of Ti 3 C 2 T x. Furthermore, the interlayer can protect the Lithium metal anode by preventing polysulfide from depositing on the anode surface. Accordingly, the TOS/MX/TOS interlayer exhibits excellent performance with stable long-term cycling (≈76.1% capacity retention with a decay rate of 0.048% per cycle after 500 cycles at 1C). This sandwiched interlayer with high discharge capacity and steady cycling performances is conducive to the practical application of lithium-sulfur batteries. [Display omitted] [ABSTRACT FROM AUTHOR]

In this article, a miniaturized bandpass filter with improved stopband using a short-circuit centered stepped impedance resonator is presented. An extra transmission zero can be provided near the passband for good frequency selectivity by introducing mixed electric/magnetic coupling in the proposed filter. Multiple transmission zeros are introduced in the upper stopband via, taking advantage of the harmonic effects of the distributed transmission line. Meanwhile, source-load coupling is introduced to improve the skirt selectivity via shifting the transmission zeros to the vicinity of the passband. The odd- and even-mode analytical method is used to design the filter. To verify the validity of the proposed technique, the new bandpass filter has been analyzed, simulated, and fabricated. The measurement results agree well with the full-wave electromagnetic designed responses. [ABSTRACT FROM PUBLISHER]

In this study, we used lead zirconate titanate (PZT) aerogels prepared by a solvothermal assisted sol–gel method as raw materials to synthesize PZT aerogel/PVDF composite coatings and PZT aerogel sintered sheets through natural annealing and PVDF composite and hot pressing, respectively, and then combined them with the design principle of a biomimetic shell structure to prepare an alternate coating/sheet structured PZT aerogel piezoelectric composite with natural distinguished mechanical properties. It had excellent piezoelectric properties with a piezoelectric coefficient d33 of 435.15 pC N−1 and d31 of −144.55 pC N−1, excellent electromechanical coupling properties with a planar electromechanical coupling coefficient of 60.14%, low dielectric loss of 0.76% at 40 Hz and low density of 3.04 g cm−3. When used as the piezoelectric material in underwater acoustic transducers (UATs), compared with all kinds of piezoelectric ceramics, it achieved higher piezoelectric and comprehensive mechanical properties, lower dielectric loss, lower density, and electromechanical coupling properties similar to that of Pb-containing piezoelectric ceramics, thus showing extremely promising application prospects in UATs. [ABSTRACT FROM AUTHOR]

Aberrant signaling via fibroblast growth factor 19 (FGF19)/fibroblast growth factor receptor 4 (FGFR4) has been identified as a driver of tumorigenesis and the development of many solid tumors, making FGFR4 is a promising target for anticancer therapy. Herein, we designed and synthesized a series of bis-acrylamide covalent FGFR4 inhibitors and evaluated their inhibitory activity against FGFRs, FGFR4 mutants, and their antitumor activity. CXF-007 , verified by mass spectrometry and crystal structures to form covalent bonds with Cys552 of FGFR4 and Cys488 of FGFR1, exhibited stronger selectivity and potent inhibitory activity for FGFR4 and FGFR4 cysteine mutants. Moreover, CXF-007 exhibited significant antitumor activity in hepatocellular carcinoma cell lines and breast cancer cell lines through sustained inhibition of the FGFR4 signaling pathway. In summary, our study highlights a novel covalent FGFR4 inhibitor, CXF-007 , which has the potential to overcome drug-induced FGFR4 mutations and might provide a new strategy for future anticancer drug discovery. [Display omitted] • The covalent inhibitor CXF-007 demonstrated the greatest potency against FGFR4. • CXF-007 has the potential to overcome acquired FGFR4 cysteine mutants. • CXF-007 selectively inhibits and interacts more with FGFR4. • CXF-007 potently inhibits proliferation and FGFR4 signaling in cancer cell lines. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries are deemed as optimal energy devices for the next generation of high‐energy‐density energy storage. However, several problems such as low energy density and short cycle life hinder their application in industry. Here, MoS2–MoN heterostructure nanosheets grown on carbon nanotube arrays as free‐standing cathodes are reported. In this heterostructure, MoN works as a promoter to provide coupled electrons to accelerate the redox reaction of polysulfides while the MoS2, with a two‐dimensional layered structure, provides smooth Li+ diffusion pathways. Through their respective advantages, both MoN and MoS2 could mutually boost the process of "adsorption‐diffusion‐conversion" of polysulfides, which have a synergy enhancement effect to restrain the lithium polysulfides from shuttling. The designed cathodes show excellent long‐term cycling performances of 1000 cycles at 1C with a low decay rate of 0.039% per cycle and a high rate capability up to 6C. A high initial areal capacity of 13.3 mAh cm−2 is also achieved under a low electrolyte volume/sulfur loading (E/S) ratio of 6.3 mL g−1. This strategy of promoting polysulfide conversion by heterostructure MoS2–MoN as presented in this work can provide a more structured design strategy for future advanced Li–S energy storage systems. [ABSTRACT FROM AUTHOR]

Abstract In the past four years, transition metal vanadates have received booming attention as anode materials for lithium ion batteries (LIBs) due to their outstanding specific capacities, decent cycling performance and superior rate properties. Among them, Co 3 V 2 O 8 is the most reported species. However the cobalt is expensive, thus the replacement of cobalt would be a favorable route. So far, mixed vanadates have been rarely reported because of the remarkable difficulty in fabrication, among which cobalt/nickel mixed vanadates are the most attractive. In this work, a facile and green hydrothermal method with organic linker has been developed, to achieve modulated cobalt/nickel mixtures. It was corroborated by the X-ray diffraction (XRD) patterns and cyclic voltammetry (CV) profiles that single phase of cubic Co 3 V 2 O 8 crystal structures were formed. The mixed vanadates demonstrated ultrahigh reversible capacity of over ∼1800 mAh/g at the current density of 0.2 A/g after ∼200 cycles and superb rate capability of ∼600 mAh/g at 4 A/g. The enhanced electrochemical performances of the higher-nickel-ratio indicated their considerable potential as high-capacity anode materials in LIBs. Graphical abstract Image 1 Highlights • Cobalt/nickel mixed vanadates were obtained via one-step and green hydrothermal process. • The mixed vanadates maintain the cubic crystal of Co 3 V 2 O 8 with nickel doping. • Higher concentration of doped nickel induced uniform nanoparticles smaller than 100 nm. • CoNi 2 V 2 O 8 delivered reversible capacity of 1800 mAh/g at 0.2 A/g and 600 mAh/g at 4 A/g. [ABSTRACT FROM AUTHOR]

Room-temperature sodium-ion batteries have attracted great attentions for large-scale energy storage applications in renewable energy. However, exploring suitable anode materials with high reversible capacity and cyclic stability is still a challenge. The VS4, with parallel quasi-1D chains structure of V4+(S22-)2, which provides large interchain distance of 5.83 Å and high capacity, has showed great potential for sodium storage. Here, the uniform cuboid-shaped VS4 nanoparticles are prepared as anode for sodium-ion batteries by the controllable of graphene oxide (GO)-template contents. It exhibits superb electrochemical performances of high-specific charge capacity (≈580 mAh·g-1 at 0.1 A·g-1), long-cycle-life (≈98% retain at 0.5 A·g-1 after 300 cycles), and high rates (up to 20 A·g-1). In addition, electrolytes are optimized to understand the sodium storage mechanism. It is thus demonstrated that the findings have great potentials for the applications in high-performance sodium-ion batteries. [ABSTRACT FROM AUTHOR]

As recently explored lithium-ion battery (LIB) anode materials, transition metal vanadates have attracted much attention due to their excellent electrochemical performance. In this work, we successfully synthesized solid Co3V2O8 microspheres (sCVO MSs) via a facile and controllable hydrothermal reaction, and the magical formation mechanism was also revealed by the different morphologies of sCVO MSs at different reaction times. When tested as LIB anode materials, sCVO MSs showed superior reversible capacities (∼780 mA h g−1 after 250 cycles at 1000 mA g−1 and as high as 550 mA h g−1 even after 400 cycles at 5000 mA g−1) and excellent rate performance (a capacity of ∼500 mA h g−1 at a current density of 2000 mA g−1). It is accordingly demonstrated that uniform sCVO MSs have great potential to be used as high-performance LIB anodes. [ABSTRACT FROM AUTHOR]

Cobalt vanadates have been demonstrated as superior anode candidates for lithium ion batteries (LIBs) owing to their unique advantages, such as superb specific capacity, low operating potential, and excellent cycling stability. Among the cobalt vanadates, Co 3 V 2 O 8 manifests tremendous potential of commercialization because of their controllable particle size and morphology. In this study, we readily synthesized both hollow and solid Co 3 V 2 O 8 micro-pencils and thoroughly compared their electrochemical properties. Employed as anode for LIBs, the hollow Co 3 V 2 O 8 exhibited much higher initial specific capacity than the solid ones (∼1200 mAhg −1 vs. ∼680 mAhg −1 ). When tested at 1000 mAg −1 , the hollow Co 3 V 2 O 8 displayed superior reversible capacity over the solid ones (∼650 mAhg −1 vs. ∼450 mAhg −1 after 300 cycles), benefiting from the hollow architecture. Moreover, the hollow micro-pencils showed better rate performance, with outstanding stability and capacity loss when higher current density was applied. The comparative study demonstrated the hollow Co 3 V 2 O 8 is more efficient than the solid ones for LIB anodes. Based on the comparison on pure micro-pencils, further approach (e.g. graphene coating) can be exploited for superior performance towards ultimate application in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Transition metal vanadates have attracted much attention for high capacity anodes of lithium ion batteries (LIBs). However, they have obvious drawbacks (short cycle-lives and low rate performance) because of the intrinsically low electronic conductivity and serious volume variation during Li-ion desorption and insertion. In particular, pure Co3V2O8 micro-pencils (pCVO MPs) have a stable and regular crystal structure, large tap density and uniform grain size, but, unfortunately, they have not exhibited expected electrochemical performance. Herein, we report the successful preparation of reduced graphene oxide coated Co3V2O8 micro-pencils (rGO@CVO MPs) through a facile approach combining hydrothermal synthesis with thermal reduction. When tested as anodes for LIBs, rGO@CVO MPs exhibit superior electrochemical performance compared to that of pure Co3V2O8 micro-pencils (pCVO MPs). The anodes of rGO@CVO MPs show a high reversible capacity of 760 mA h g−1 over 200 cycles at 200 mA g−1, and 500 mA h g−1 can remain after 500 cycles at 1000 mA g−1, with an increase in 200 mA h g−1 in contrast to the pCVO MPs. It is consequently demonstrated that the composite material (rGO@CVO MPs) is a promising anode material for LIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • A polybenzoxazine aerogel system with high strength under suitable deformation is designed. • Reversible sacrificial hydrogen bonding enhanced mechanical properties of the polybenzoxazine aerogel are realized. • The polybenzoxazine aerogel withstands more than 300,000 times its own weight under pressure before breaking. • The polybenzoxazine aerogel has a low thermal conductivity of 0.03012 W/(m·K) at 25 °C and 0.03486 W/(m·K) at 150 °C. • The polybenzoxazine aerogel has a hydrophobic angle of 148.7° and a saturated mass moisture absorption rate of about 0.63%. Aerogels are a very attractive class of lightweight and high-efficient thermal insulators, but poor mechanical properties have always been the main obstacle restricting their development and application. In order to overcome this problem, we innovatively used the concept of reversible sacrificial hydrogen bondings strengthening, and successfully synthesized a polybenzoxazine aerogel with outstanding mechanical properties and a lightweight structure. The aerogel (density 0.231 g/cm3 and porosity 90.7 %) exhibits a high compression strength of 14.36 MPa with a suitable deformation capacity of 19.6 % fracture strain, and also shows a relatively good fatigue resistance. In addition, the aerogel has outstanding thermal insulation properties [0.03012 W/(m·K) at 25℃ and 0.03486 W/(m·K) at 150℃] and hydrophobic properties (hydrophobic angle 148.7° and saturated mass moisture absorption rate about 0.63 %), thus it has great prospects for a high-efficiency thermal insulator used in buildings, industries, aerospace vehicles, etc. [ABSTRACT FROM AUTHOR]

A near-record-efficiency of 21.3% on dopant-free silicon solar cell has been achieved with transparent and low work function LiF x /MgF x O y electron-selective contact in our recent work. In this paper, the detailed formation of LiF x /MgF x O y and the influence of surface and interface characteristics on contact resistance, cell performances are systematically investigated. Scanning electron microscopy (SEM) images indicate that appropriate thickness of Mg layer can improve the surface status and facilitate good ohmic contact. Post-annealing treatment can further smooth the pyramid surface and improve the interface properties. The insertion of ultra-thin LiF x film can produce an effectively back-surface-field and promote electron-selective transport without deteriorating contact resistance. The scanning transmission electron microscopy (STEM) results further prove the in-situ inter-atomic diffusion of Fluorine (F) and Oxygen (O) at the LiF x /Mg interface, forming the LiF x /MgF x O y hybrid film stacks. As a proof-of-concept, the dopant-free silicon solar cells are fabricated with LiF x /MgF x O y electron-selective contact, achieving an impressive cell efficiency of> 21%. The formation of F and O co-diffused electron-selective contact presents a great potential for high-efficiency dopant-free silicon solar cells and perovskite solar cells application. • The formation of LiF x /MgF x O y and the influence of surface and interface on devices performances are investigated. • The in-situ inter-atomic diffusion of Fluorine (F) and Oxygen (O) at the LiF x /Mg interface is discussed. • An impressive efficiency of>21% with LiF x /MgF x O y is achieved, which has over 6% absolutely efficiency gain. [ABSTRACT FROM AUTHOR]

Substitution of expensive silver paste becomes essential for mass production of silicon heterojunction (SHJ) solar cell, which calls for high efficiency and low-cost metallization techniques. Copper metallization together with multi-busbar cell interconnection is considered as effective way to low shading loss and electrode ohmic loss. While, the electrode adhesion and parasitic plating are the key process challenges limiting the copper metallization of SHJ solar cells. In this research, the copper plated SHJ solar cells with high electrode aspect ratio and an efficiency of 23.35% have been achieved on M2 wafers. The SEM images show the holes in the plated layers will deteriorate the adhesion between plated copper and seed-layer. The glass/back sheet structure (GBS) modules have been laminated to evaluate the influence of parasitic plating on damp-heat (DH) performance. The degradation in output power (P max) is up to 4.90%, which is primarily due to a decreased open-circuit voltage (V oc) and fill factor (FF). It can be ascribed to the deteriorated surface recombination and interconnection. Although the parasitic plating on the wafer edge has ignorable influence on damp heat test after etch-back process, it is still necessary to protect the cell edge to avoid parasitic plating. The research evaluates the process challenges of copper metallization of SHJ solar cells, which offers a refer for achieving high reliability and low levelized cost of energy (LCOE) of photovoltaic power generation. • This work evaluates the challenge of ghost plating on high-performance SHJ solar cells and modules for the first time. • The surface morphology and element distribution at the interface is analyzed and an efficiency of 23.35% is obtained. • The glass/back sheet modules have been laminated to evaluate the influence of ghost plating on damp-heat (DH) performance. [ABSTRACT FROM AUTHOR]

Lead zirconate titanate (PZT) aerogels are ideal piezoelectric materials for underwater acoustic transducers (UATs) due to their light structure, but their difficult preparation, poor mechanical properties and poor integrated electrical properties greatly limit their practical applications. In order to overcome these difficulties, we innovatively adopted a solvothermally combined sol-gel method to successfully achieve simple, rapid, and low-cost preparation of PZT aerogels, designed a 0–3 type PZT aerogel/PVDF composite coating to overcome the weak mechanical properties of PZT aerogels, and used SiO 2 aerogels and PZT ceramic powders to improve the ferroelectric and piezoelectric properties of the PZT aerogel/PVDF composite coating, respectively. After verifying that the PZT aerogel/PVDF composite coating modified by 4 wt% SiO 2 aerogels and 30 wt% PZT ceramic powders has the best integrated electrical properties, we prepared its 50-layer combination to further improve the comprehensive properties. The 50-layer composite coating has a moderate piezoelectric constant d 33 of 132.7 pC/N and a high piezoelectric constant d 31 of −33.6 pC/N, a low relative permittivity of 593.7 and a low dielectric loss of 0.85% at 40 Hz, a high Young's modulus of 616.2 MPa, and a density of 1.163 g/cm3 similar to water, indicating that it has surpassed various high-performance Pb-containing piezoelectric ceramics in integrated electrical properties, mechanical properties and acoustic impedance matching with water, which is more in line with the needs of use in UATs. This research offers a new pathway to design a piezoelectric material for UATs with light structure and excellent comprehensive properties. • Solvothermal combined with sol-gel method overcomes the bottleneck that PZT aerogels are difficult to prepare. • PZT aerogel/PVDF composite coating is used to overcome the poor mechanical properties of PZT aerogels. • SiO 2 aerogels and PZT ceramic powders improve the ferroelectric and piezoelectric properties of the composite coating. • The 50-layer composite coating realizes light structure, excellent mechanical and integrated electrical properties. • The 50-layer composite coating shows extremely superior practical significance for UATs. [ABSTRACT FROM AUTHOR]

A practical and effective strategy of phosphoric acid treatment is developed to obtain a modified LRMO containing Li-poor layer, PO 4 3− doping, and layer-spinel mosaic composite structure. The vacancy energy and crystal structure stability of LRMO are improved effectively. As results, the modified LRMO exhibits enhanced electrochemical performance, especially inhibiting voltage decay and oxygen evolution. [Display omitted] • A practical and effective chemical treatment strategy for Li-rich Mn-based oxides. • Li-poor layer reduces irreversible Li+. • PO 4 3− doping improves the vacancy energy. • Layer-spinel mosaic composite structure stabilizes the voltage platform. Li-rich Mn-based oxides (LRMOs) are promising high energy–density cathodes, but the low initial Coulombic efficiency (ICE), voltage attenuation and oxygen evolution hinder the commercialization of LRMOs. Here, we incorporate acid radical ion into materials' lattices to construct a LRMO with gradient ion concentration and layer-spinel mosaic structure via a practical and controllable strategy of chemical de-lithium route. The experimental and theoretical analyses demonstrate that the phosphate radical (PO 4 3−) enter the lattice to enhance the vacancy energy of the material, which can improve the structural stability, inhibit oxygen evolution and voltage decay. As results, the best modified LRMO (PTS-20) exhibits suppressed voltage decay (∼27.16 mV at 1 C after 200 cycles) and higher initial discharge specific capacity of 283.5 mAh g−1 at 0.05 C with high ICE of 95.4%. In-situ differential electrochemical mass spectrometry (DEMS) further demonstrate that PTS-20 has less oxygen evolution. Furthermore, full cells assembled with graphite behave excellent electrochemical performances at 1 C. This work provides an effective strategy to fabricate LRMO cathodes with promising practical electrochemical performances. [ABSTRACT FROM AUTHOR]

Vanadium oxide thin films have been deposited by reactive DC magnetron sputtering. The results showed that the sputtering voltage has a special change behavior in Ar condition and Ar/O2mixed conditions. With O2gas flow input instantaneously, the sputtering voltage climbs quickly, and then tends to be stable shortly. Also, the sputtering voltage evolution appears a hysteretic loop characteristics with O2gas supplied increasing and decreasing. The sputtering voltage behavior observed is related to the ion induced secondary electron emission (ISEE) coefficient of the target material. The ISEE coefficient of the oxidized vanadium on target surface is lower than the ISEE coefficient of the pure vanadium metal, which is not in agreement with the generally accepted idea that the ISEE coefficient of oxides is much larger than for metals. [ABSTRACT FROM AUTHOR]

Abstract: Ba0.6Sr0.4TiO3 thin films were deposited on Pt/SiO2/Si substrate by radio frequency magnetron sputtering. High-resolution transmission electron microscopy (HRTEM) observation shows that there is a transition layer at BST/Pt interface, and the layer is about 7–8nm thickness. It is found that the transition layer was diminished to about 2–3nm thickness by reducing the initial RF sputtering power. X-ray photoelectron spectroscopy (XPS) depth profiles show that high Ti atomic concentration results in a thick interfacial transition layer. Moreover, the symmetry ν of ɛ r–V curve of BST thin film is enhanced from 52.37 to 95.98%. Meanwhile, the tunability, difference of negative and positive remanent polarization (P r), and that of coercive field (E C) are remarkably improved. [Copyright &y& Elsevier]

• Sulfur host prepared by a unique dual-channel electrospinning method. • WS 2 /WO 3 and MoS 2 /MoO 3 heterostructures enabling anchor of LiPSs. • WX 2 and MoX 2 realized LiPSs adsorption and catalytic conversion. • Excellent energy storage performance is in both coin cell and pouch cell. Due to the dissolution of Lithium polysulfides (LiPSs), the volume expansion, and poor conductivity, practical applications of Lithium-sulfur batteries (LSBs) are not satisfactory. Herein, dual-heterostructure decorated interweaved carbon nanofibers are proposed as sulfur hosts to significantly improve the energy storage behavior of LSBs. The unique structure of the interweaved carbon nanofibers and heterostructures provides more transmission channels for electrons and ions while also accelerating the process. Moreover, the heterostructures induce chemical anchoring and catalytic conversion of LiPSs. As a result, the cathode in the coin cell delivers an initial capacity of 777.9 mAh g−1 at 1C and high retention of 68.59% after 600 cycles. In the pouch cell, the cathode delivers a discharge capacity of 907.8 mAh g−1 and a reversible charging capacity of 913.1 mAh g−1 for the first cycle with an ultra-high sulfur loading up to 9.136 mg cm−2. Beyond that, density functional theory calculations, X-ray photoelectron spectroscopy, symmetric cell, and Li 2 S nucleation tests were adopted to verify the adsorption and catalytic conversion mechanisms of the cathode. This excellent interweaved dual-heterostructure sulfur host provides a novel structural design strategy for efficient chemical adsorption and catalytic conversion of LiPSs, as well as more opportunities for the commercial application of LSBs. [ABSTRACT FROM AUTHOR]