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The aim of achieving integration of lightweight, high strength, high‐temperature resistant, and satisfactory electromagnetic (EM) wave absorption was successfully accomplished in the present study by synthesizing TiC–TiB2 fibers reinforced Si3N4 composites, which were pressureless sintered at 1650°C for 2 h. The preparation of TiC–TiB2 fibers was conducted through a chloride‐assisted carbothermic method. This work focused on investigating the effects of incorporating TiC–TiB2 fibers on the mechanical properties and EM wave absorption characteristics of the composites. The 30 wt% TiC–TiB2/Si3N4 composite displayed the bulk density of 1.89 g/cm3, bending strength of 93.11 ± 3.91 MPa, fracture toughness of 1.81 ± 0.10 MPa m1/2, minimum reflection loss of −38.87 dB, and effective absorption bandwidth of 1.43 GHz in the Ku‐band, respectively. The as‐synthesized TiC–TiB2/Si3N4 composites are promising candidates for EM wave absorbing load‐bearing materials due to their outstanding mechanical properties and microwave absorption properties. [ABSTRACT FROM AUTHOR]

In this study, a chloride-assisted boro/carbothermal reduction method was employed to prepare HfB 2 whiskers, aiming to address the challenges associated with large-scale preparation of HfB 2 whiskers and the development of high-temperature resistant electromagnetic wave absorbing materials. When the precursors were mechanically stirred, the resulting mixture underwent calcination at 1450 °C for 3 h, leading to the formation of single-phase HfB 2 whiskers. The as-synthesized HfB 2 whiskers showed exceptional resistance to oxidation at temperatures up to 700 °C. The microwave absorption performance and mechanism of the HfB 2 whiskers/paraffin composite were also investigated. The results revealed that the composite achieved a minimum reflection loss of −41.29 dB when the HfB 2 whiskers content reached 80 wt%, while the widest effective absorption bandwidth of the composite reached 3.6 GHz when the HfB 2 whiskers content increased to 82.5 wt%. This work presents a novel candidate for high-temperature resistant materials used in absorbing electromagnetic wave. [ABSTRACT FROM AUTHOR]

In this study, a chloride-assisted boro/carbothermal reduction method was employed to prepare HfB 2 whiskers, aiming to address the challenges associated with large-scale preparation of HfB 2 whiskers and the development of high-temperature resistant electromagnetic wave absorbing materials. When the precursors were mechanically stirred, the resulting mixture underwent calcination at 1450 °C for 3 h, leading to the formation of single-phase HfB 2 whiskers. The as-synthesized HfB 2 whiskers showed exceptional resistance to oxidation at temperatures up to 700 °C. The microwave absorption performance and mechanism of the HfB 2 whiskers/paraffin composite were also investigated. The results revealed that the composite achieved a minimum reflection loss of −41.29 dB when the HfB 2 whiskers content reached 80 wt%, while the widest effective absorption bandwidth of the composite reached 3.6 GHz when the HfB 2 whiskers content increased to 82.5 wt%. This work presents a novel candidate for high-temperature resistant materials used in absorbing electromagnetic wave. [ABSTRACT FROM AUTHOR]

Compared with common monoanionic high entropy ceramics, polyanionic high entropy ceramics, with better performance, are more difficult to prepare. Since transition metal carbides have high hardness and transition metal nitrides have good toughness, it is hoped that high entropy carbonitride ceramics can combine the advantages of the two. In this paper, a series of novel (Ti 0.25 Nb 0.25 Hf 0.25 Ta 0.25)C x N 1–x (x = 0.3, 0.4, 0.5, 0.6, and 0.7) high entropy ceramics were successfully synthesized for the first time using spark plasma sintering at 1850 °C with metal carbides and metal nitrides as raw materials. The phase evolution, microstructure, hardness and fracture toughness of high carbonitride entropy ceramics were investigated. X-ray diffraction indicates the ceramics with the single-phase face-centered cubic structure were successfully prepared. It was found that the high entropy ceramics sintered at 1850 °C with four cationic components have excellent performance on fracture toughness (KIC = 7.1746 MPa m1/2). With the increase of carbide proportion, the hardness of the ceramics increased, but the fracture toughness and bending strength decreased slightly. And it was found that the differences of grain size and porosity content were the main reasons for the mechanical properties difference. The excellent hardness properties, good bending strength and outstanding fracture toughness of the high entropy ceramics provide the possibility for the application of high entropy ceramics in aerospace and other applications requiring high performance. [ABSTRACT FROM AUTHOR]

Nowadays, the increasingly severe electromagnetic (EM) wave pollution requires high-performance EM wave absorbing materials. Multi-principal-element materials are acknowledged as promising for broadening the applications owing to their tunable chemistries and structures in many fields, including as EM wave absorbers. Herein, we prepared a high-entropy MXene, (Mo 0.25 Cr 0.25 Ti 0.25 V 0.25) 3 C 2 T x. Furthermore, multi-principal-element (Mo 0.25 Cr 0.25 Ti 0.25 V 0.25) 3 C 2 T x /FeCoNi and (Mo 0.25 Cr 0.25 Ti 0.25 V 0.25) 3 C 2 T x /FeCoNiCu composites were synthesized via an in-situ hydrothermal process by combining high-entropy MXene with medium-entropy magnetic alloys. In contrast with the relatively narrow effective absorption bandwidth (EAB) of (Mo 0.25 Cr 0.25 Ti 0.25 V 0.25) 3 C 2 T x MXene (2.56 GHz), (Mo 0.25 Cr 0.25 Ti 0.25 V 0.25) 3 C 2 T x /FeCoNi composite with 50 wt% MXene can attain an optimum EAB of 4.88 GHz with the matching thickness of only 1.73 mm. As for (Mo 0.25 Cr 0.25 Ti 0.25 V 0.25) 3 C 2 T x /FeCoNiCu composites, both the absorption efficiency and absorption bandwidth are significantly enhanced. The combination of multi-principal-component strategy and composite construction endows the composites with synergistic dielectric and magnetic losses, optimized impedance matching as well as enhanced attenuation ability, thus improving EM wave absorption performances. In addition, radar cross section (RCS) simulation confirms that the prepared composites have broad application prospects as radar stealth materials. [ABSTRACT FROM AUTHOR]

In view of the lack of conformal, load‐bearing, light‐weight, and high temperature‐resistant integrated wave‐absorbing composites suitable for extremely complex conditions, the gel‐casting process was successfully applied to porous Si3N4 wave‐absorbing composites in this work. A universal low‐slurry for gel casting was prepared by using two dispersants acting together (tetramethylammonium hydroxide solution and sodium lauryl sulfate), which ensured the smooth completion of the gel casting process. Combining the thermogravimetric and differential thermal gravity curves of the composite green body, reasonable parameters of the rubber discharge process are given to avoid the problem of the green body swelling and cracking. The porous TiC/Si3N4 composites were successfully prepared by holding them at 1650°C for 3 h. The bending strength, density, minimum reflection loss, absorption bandwidth, and matched thickness in the P‐band of the composites with 30 wt.% TiC addition were 54.08 ± 3.02 MPa, 1.906 g/cm3, ‐37.75 dB, 1.9 GHz, and 4.1 mm, respectively. The electromagnetic wave loss mechanisms of the composites are a combination of conductivity loss, multiple reflections and scattering, interfacial polarization, and defect polarization. [ABSTRACT FROM AUTHOR]

The relationship between the chemical elements of high-entropy boride (HEB) ceramics and their hardness is important for the prediction of high-hardness HEB ceramics. In this work, by designing four HEB ceramics with different chemical elements, the effect of lattice parameter difference factor (δ, represents the difference-degree in lattice parameters among the five individual constitute diborides) on phase composition and lattice-distortion, and the effect of rule of mixture (ROM) average hardness and lattice-distortion on HEB ceramics hardness were studied. The results indicated that, as δ value increases, more severe lattice-distortion occurs inside the HEB ceramics, and a single solid-solution is difficult to be formed. Furthermore, lattice-distortion and the ROM average hardness codetermine the HEB ceramics hardness. The greater lattice-distortion brings about significantly higher hardness for HEB ceramics than their ROM average hardness. Among the four HEBs, (Hf 0.2 Zr 0.2 Ta 0.2 V 0.2 Nb 0.2)B 2 exhibits the high hardness of 26 GPa measured using a load of 9.8 N. [ABSTRACT FROM AUTHOR]

In view of the lack of a conformal, load-bearing, lightweight, and high-temperature resistant integrated microwave-absorbing composites for applications under extremely complex conditions, this study successfully applies gel casting craft to porous Si 3 N 4 microwave-absorbing composites. The high-temperature decomposition reaction of Ti 3 SiC 2 powder was utilized to generate uniform Ti-C x -N 1−x grains in situ and to enhance the mechanical and microwave-absorption properties of porous Ti-C x -N 1−x /Si 3 N 4 composites. The bending strength, fracture toughness, density, maximum reflection loss value, absorption bandwidth and matched thickness in P-band of the composite with 30 wt% Ti 3 SiC 2 addition were 164.87 ± 7.56 MPa, 2.61 ± 0.13 MPa·m1/2, 2.077 g/cm3, 32.42 dB, 1.74 GHz and 4.2 mm, respectively. The fracture toughness and bending strength of the composite were increased by 71.71% and 58.13%, respectively, compared with monolithic porous Si 3 N 4. The electromagnetic wave loss mechanisms of the composites are proposed as a combination of conductivity loss, multiple reflections and scattering, interfacial polarization and defect polarization. [ABSTRACT FROM AUTHOR]

The TiB 2 fibers were prepared by a chloride-assisted carbothermic method accompanied with the vapor-liquid-solid (VLS) mechanism. The influences of TiO 2 , B 2 O 3 , C 12 H 22 O 11 , and calcination temperature on the yield of TiB 2 fibers were investigated. In addition, the effects of TiB 2 fibers content on the electromagnetic (EM) parameters and microwave absorption (MA) properties of TiB 2 fibers/paraffin composite was studied in detail. The TiB 2 fibers/paraffin composite showed excellent microwave absorption performance, with an optimized reflection loss (RL) of −46.63 dB at 14 GHz and a thickness of 1.5 mm. Moreover, it exhibited a broad effective absorption bandwidth (EAB) (RL < −10 dB) of 3.9 GHz, ranging from 12 to 15.9 GHz. TiB 2 fibers exhibit promising potential as materials for high-temperature applications in the field of MA. [ABSTRACT FROM AUTHOR]

In the recent years, MXenes (2D transition metal carbides, carbon nitrides and nitrides) and its precursor MAX phases have been widely investigated in electrochemical research. In this research, we successfully prepared a core-shell structured compound——Ti 3 C 2 @Ti 2 SnC/CNFs (MXene@TSC/C) as an anode material for lithium ion battery via electrospinning method. Results showed that this type of compound has a specific capacity of 288.9 mAh·g−1 at the current density of 0.4 A g−1 after 300 cycles, accompany with a retention rate of capacity of 105.4% in the rate performance test. These performances were benefit from the core-shell structured CNFs and Ti 3 C 2 MXenes. This work supported a novel way to improve the electrochemical property of MXene and MAX phases, which was expected to further explored. [ABSTRACT FROM AUTHOR]

A sol-gel method was employed for the synthesis of new High-entropy boride (HEB) powders, (Hf 0.2 Nb 0.2 Cr 0.2 Ta 0.2 Mo 0.2)B 2 , with nanoscale. The as-synthesized powders were obtained at a relatively low temperature of 1650 °C, and had small average particle size of 62.09 nm. X-ray diffraction confirmed that the (Hf 0.2 Nb 0.2 Cr 0.2 Ta 0.2 Mo 0.2)B 2 powders were hexagonal single-phase without any oxide impurities. In particular, electrochemical performance of the (Hf 0.2 Nb 0.2 Cr 0.2 Ta 0.2 Mo 0.2)B 2 powders with multiphase and high-entropy single phase were investigated using a three-electrode system. The improved electrochemical performance of the HEB powders is realized, with 27% higher in specific capacitance compared to the powders with multiphase. The HEB powders electrode exhibits a high capacitance retention of 97.03% after 5000 cycles. [ABSTRACT FROM AUTHOR]

The new inorganic material known as "high-entropy oxides" (HEOs) has a single-phase structure and is made up of several different main metal elements. It has many useful properties, including a high specific capacity, excellent cycling performance, high structural stability, and super-electronic conductivity. For lithium-ion batteries, it is viewed as a promising electrode material (LIBs). It is significant to develop high entropy oxides with different components and study their properties. Herein, Mg, Ni and Li are added to the quaternary medium entropy (CrFeMnCo)3O4. Four new spinel high entropy oxides were synthesized by glycine-nitrate SCS method at 750 °C and their material characterization and electrochemical properties were investigated respectively. The experimental results show that the four obtained samples have uniform particle size distribution. As for the electrochemical test, the capacities of the (CrFeMnCoMg)3O4 and (CrFeMnCoNi)3O4 do not decrease significantly after 800 cycles at 2000 mA·g−1. They have better cycle stability than the (CrFeMnCoMgLi)3O4 and (CrFeMnCoNiLi)3O4. As the anode of LIBs, all HEOs show excellent cycle stability and rate capability. This work provides a new strategy for designing high-entropy energy storage materials. [ABSTRACT FROM AUTHOR]

The present study investigated the dose-dependent effect of inositol on the thermally induced crystallization and phase evolution of amorphous calcium phosphate. It has been demonstrated that the crystallization of amorphous calcium phosphate was postponed by the introduction of inositol. The initial crystallize phase under 600 °C and thermodynamic equilibrium between α/β-tricalcium phosphate (TCP) under higher temperatures were altered in a content-dependent manner. Smaller amounts of inositol could promote the formation of α-TCP-like hydroxyapatite and expand the annealing temperature range to obtain pure α-TCP, while larger amounts would exhibit the opposite effect and promote the formation of β-TCP. This discovery could be used to guide the production of α/β-TCP. [ABSTRACT FROM AUTHOR]

The composition and synthesis approach of high entropy ceramics have significant influences on their microstructures and mechanical properties. A new (Hf 0.2 Zr 0.2 Ta 0.2 V 0.2 Nb 0.2)B 2 high entropy diboride ceramic with excellent mechanical properties was successfully prepared by spark plasma sintering (SPS) at a relatively "low temperature" (1800 °C) in this work. The effects of two mixing strategies, grinding and ball milling, on the solid solubility of the calcined powders were studied. Furthermore, the effects of these two mixing strategies on the phase and morphology of the calcined powders and the mechanical properties of the SPS sintered ceramics were analyzed. Experimental results indicated that, compared with a single solid solution phase within the high entropy boride powders obtained by ball milling, incomplete solid-solution presented in the high entropy boride powders obtained using grinding treatment. It promoted the solid-state diffusion and in-situ reaction of the diborides in the ceramics during the sintering process, thereby improving the densification and the hardness of the high entropy diboride ceramics. By grinding treatment, (Hf 0.2 Zr 0.2 Ta 0.2 V 0.2 Nb 0.2)B 2 high entropy ceramic with a relative density of 94% and a hardness of up to 25.34 ± 1.5 GPa at an indentation load of 9.8 N was obtained at 1800 °C. This work not only expanded the family of high-entropy diboride ceramics but also proved the advantage of grinding treatment in preparation of high entropy diboride ceramics. [ABSTRACT FROM AUTHOR]

The boron nitride nanosheets (BNNSs)/aluminum nitride (AlN) composites were prepared by hot press sintering at 1600°C. The microstructure, mechanical properties, and thermal conductivity of the samples were measured, and the effect of adding BNNSs to AlN ceramics on the properties was studied. It is found that the addition of BNNSs can effectively improve the mechanical properties of AlN. When the additional amount is 1 wt%, the bending strength of the sample reaches the maximum value of 456.6 MPa, which is 23.1% higher than that of the AlN sample without BNNSs. The fracture toughness of the sample is 4.47 MPa m1/2, a 68.7% improvement over the sample without BNNSs. The composites obtained in the experiment have brilliant mechanical properties. [ABSTRACT FROM AUTHOR]

Biphasic calcium phosphate (BCP) is an important research field based on calcium phosphate biomaterials. In this paper, a new synthesis method of CDHA/α-TCP BCP was studied. By controlling the addition amount of citric acid, the relative contents of CDHA and α-TCP in the BCP were controlled. BCP bone cement was prepared with different proportions of BCP as raw materials. The BCP bone cement was characterized by XRD and SEM, and evaluated by measuring setting time, compressive strength, SBF immersion, and colorimetric CCK-8 assay. The results showed that the increase of CDHA content can lead to the reduction of the setting time of bone cement and delay the degradation rate of BCP bone cement. [ABSTRACT FROM AUTHOR]

The fracture toughness and oxidation resistance are crucial factors affecting the practical applications of high-entropy diboride ceramics (HEBs). In this study, silicon carbide whiskers (SiC w) were introduced as a reinforcement for HEBs for the first time. To achieve a uniform dispersion of SiC w within the HEB powders, a combination of simultaneous ultrasonic dispersion, mechanical agitation, and freeze-drying technology was employed. Consequently, a series of composites, (Hf 0.2 Zr 0.2 Ta 0.2 V 0.2 Nb 0.2)B 2 -nSiC w (n = 0–20 vol%), were densified by spark plasma sintering. The effect of SiC w on the microstructure and mechanical properties of the HEBs were studied, as well as the toughening mechanism involved. The results revealed that the introduction of SiC w led to grain-size refinement in (Hf 0.2 Zr 0.2 Ta 0.2 V 0.2 Nb 0.2)B 2 , along with significant improvements in relative density, hardness, fracture toughness, and oxidation resistance. The relative density, hardness and fracture-toughness of (Hf 0.2 Zr 0.2 Ta 0.2 V 0.2 Nb 0.2)B 2 -SiC w composites exhibited an initial increase followed by a decrease with increasing SiC w content. Specifically, the (Hf 0.2 Zr 0.2 Ta 0.2 V 0.2 Nb 0.2)B 2 –15 vol% SiC w composite simultaneously obtained the highest hardness of 25.6 GPa and fracture-toughness of 4.8 MPa·m1/2, representing a 26% improvement compared to (Hf 0.2 Zr 0.2 Ta 0.2 V 0.2 Nb 0.2)B 2 ceramics. • The effect of SiC w on microstructure, mechanical properties and oxidation resistance of HEBs were studied for the first time. • The K Ic of (Hf 0.2 Zr 0.2 Ta 0.2 V 0.2 Nb 0.2)B 2 ceramic was increased by 26% without loss of hardness by introducing SiC w. • The oxidation resistance of HEBs was greatly enhanced due to the addition of SiC whiskers. [ABSTRACT FROM AUTHOR]

Compared to 1D compressed sensing (CS), 2D CS is more efficient for compressing the plaintext image from two directions, but security level of current 2D CS-based ciphers is unsatisfactory. To solve this problem, this paper presents a novel color image compression and encryption algorithm by combining 2D CS, information entropy and chaos. Firstly, the color image is decomposed into red, green and blue components, then they are sparsely transformed by the discrete wavelet transform (DWT) to get three sparse matrices. Next, the obtained matrices are observed by two asymptotical deterministic random measurement matrices based on information entropy and counter (ADMMIC), which not only encrypts the plaintext image, but also compresses it in proportion to reduce the transmission bandwidth and storage space. Subsequently, the corresponding measurement value matrices are shuffled by a double random scrambling based on Arnold map and index vector (DRSAIV) to eliminate the correlation between adjacent pixels. Furthermore, the obtained permutated matrices are diffused by a simultaneous multiple random diffusion of inter–intra components (SMRDIC) to obtain the final cipher image, the plaintext pixel to be diffused, the key matrix involved in diffusion and the position of the obtained ciphertext pixel are all unpredictable, which makes statistical attack invalid. In addition, information entropy values of plaintext image are obtained to generate the initial values of the used chaotic systems, which greatly improve the ability to resist the known-plaintext and chosen-plaintext attacks. Simulation results and security analyses verify that this algorithm has good compression and high security. [ABSTRACT FROM AUTHOR]

In this work, we synthesized K2Ti6O13 nanowires coated with sulfur-doped carbon for the first time, with fulvic acid and cystine as the carbon source, which exhibit higher capacity and rate performance compared with pure potassium titanate. Via analyzing the cyclic voltammetry curves obtained at different scan rates, it is revealed that the capacity increase is due to the improved ion diffusivity induced by the carbon coating. Moreover, cystine is demonstrated to be a better carbon source than fulvic acid. [ABSTRACT FROM AUTHOR]

Upconversion (UC) luminescence modulation is quite important in controlling and processing light for active components of light sources, photoswitches, optical memories, and optical sensing devices. In this work, we reported one kind of novel phosphor, Ho3+/Yb3+‐doped SrBi4Ti4O15 ceramics, which displayed both strong UC luminescence and obvious photochromic (PC) reaction. The UC luminescence, PC effect, and the modulation of UC performance based on PC behavior were investigated in detail. By alternating visible light irradiation and thermal stimulus, the UC luminescence could be reversibly regulated. Meanwhile, the modulation was unveiled to tightly rely on the irradiation time and thermal treatment processes. Excellent reproducibility was also achieved. In addition, as an alternative method to thermal treatment, the manipulation of luminescence by electric field was also explored. Finally, the mechanism related to the UC luminescence manipulation was illustrated. The results indicate that these samples could be potentially utilized in optical data storage and anti‐counterfeiting security fields. [ABSTRACT FROM AUTHOR]

Due to their intriguing properties, boron nitride nanosheets (BNNSs) with large lateral size and high crystallinity have great promise for many applications. However, the quantitative exfoliation of hexagonal boron nitride (h-BN) into good quality BNNSs still remains a key challenge. Herein, we report a scalable method to exfoliate BNNSs in ionic liquids (ILs) via shear-assisted thermal treatment. Few-layer BNNSs with well-preserved structural integrity are successfully prepared by this method. The synergistic effects of strong physical adsorption and intercalation of IL molecules, chemical interactions between hydrogen fluoride (HF) and h-BN, activation energy provided by heat treatment, and shear forces generated by repetitive stirring effect contribute to the exfoliation of BNNSs. [ABSTRACT FROM AUTHOR]

Strontium has been widely used in bone repair materials due to its roles in promoting osteoclast apoptosis and enhancing osteoblast proliferation. In this work, synthesis and the effects of Sr2+ doping α-tricalcium phosphate at low-temperature was studied. The setting time and the mechanical properties of α-tricalcium phosphate were controlled by varying the content of Sr2+. The synthesized compounds were evaluated by XRD, SEM, XPS, setting time, compressive strength, SBF immersion, and colorimetric CCK-8 assay. The results showed that Sr2+ can improve the compressive strength and cell activity of calcium phosphate bone cement. [ABSTRACT FROM AUTHOR]

Nickel ferrite owns a lot of advantages as electrode materials for supercapacitor, such as high energy density and excellent theoretical capacity. Whereas, the electrochemical performances of NiFe 2 O 4 in terms of rate performance and cycle stability are not satisfactory due to the low conductivity. While carbon fiber is a kind of material with high conductivity. Hence, NiFe 2 O 4 @ slit modified hollow carbon fiber is obtained through the coaxial electrospinning method. The slits on hollow carbon fibers are beneficial to the contact of inner NiFe 2 O 4 nanoparticles with electrolyte. Results of electrochemical tests show that at a current density of 1 A/g, the specific capacitance of NiFe 2 O 4 @ slit modified hollow carbon fiber is calculated to be 225.4 F/g, higher than that of NiFe 2 O 4 nanoparticles of 134.8 F/g. Moreover, a better cycle and rate performances (100 % vs 80 %; 71.9 % vs 47.5 %) are achieved. This work displays that slit modified hollow carbon fiber can improve the electrochemical performance of NiFe 2 O 4 efficiently. [Display omitted] • Carbon fibers are introduced to enhance the rate and cycle performances of NiFe 2 O 4. • Slits are obtained utilizing Al 2 O 3 sacrificial hard templates. • Slits are beneficial to the contact of NiFe 2 O 4 and electrolyte. [ABSTRACT FROM AUTHOR]

Core-shell hierarchical structured composites have demonstrated great advantages in numerous energy storage devices. In particular, structured composites with rationally structural components and controllable morphology are the most effective in enhancing electrochemical properties. In this work, MnO 2 @NiCo 2 O 4 @Ti 3 SiC 2 /CC (carbon cloth) core-shell hierarchical structured composites were designed and successfully synthesized via electrospinning followed by a two-step hydrothermal reaction. The Ti 3 SiC 2 /CC nanofibers and core-shell nanoarrays were able to improve the specific capacitance and cycling stability. In the three-electrode system, the specific capacitance of MnO 2 @NiCo 2 O 4 @Ti 3 SiC 2 /CC was observed as 1938.2 F/g at a current density of 1 A/g, while the rate capability retention was observed as 81.7% between 1 and 10 A/g. Furthermore, a superior cycling stability was observed following 5000 cycles with a specific capacitance retention rate of 55.4%. Employing MnO 2 @NiCo 2 O 4 @Ti 3 SiC 2 /CC as the all solid-state supercapacitor positive electrode exhibited a high energy density of 58.0 W h/kg at the power density of 800 W/kg. Results demonstrate the potential of the MnO 2 @NiCo 2 O 4 @Ti 3 SiC 2 /CC as an electrode material with phenomenal electrochemical properties for supercapacitors. [ABSTRACT FROM AUTHOR]

Strontium has been widely used in bone repair materials due to its roles in promoting osteoclast apoptosis and enhancing osteoblast proliferation. In this work, synthesis and the effects of Sr2+ doping α-tricalcium phosphate at low-temperature was studied. The setting time and the mechanical properties of α-tricalcium phosphate were controlled by varying the content of Sr2+. The synthesized compounds were evaluated by XRD, SEM, XPS, setting time, compressive strength, SBF immersion, and colorimetric CCK-8 assay. The results showed that Sr2+ can improve the compressive strength and cell activity of calcium phosphate bone cement. [ABSTRACT FROM AUTHOR]

Boron nitride nanosheets (BNNSs)/magnesium oxide (MgO) composites were prepared via hot pressing. Mechanical properties of MgO ceramics were improved obviously in virtue of adding BNNSs. The bending strength of the 1 wt% BNNSs/MgO composite increased by about 85% than that of the monolithic MgO. The fracture toughness increased by 34% with the addition of 1.5 wt% BNNSs. Microstructural analyzes have shown that the toughening mechanisms are combinations of the pull-out and bridging of BNNSs, crack deflection, and crack bypassing mechanisms. The addition of a small amount of BNNSs don't destroy the excellent dielectric properties of composites. The dielectric constant of the sample doped with 1 wt% BNNSs was about 9.5 in the whole X-band and the vast majority of P-band, and the loss tangent was less than 5 × 10−3 in 10–15.8 GHz. [ABSTRACT FROM AUTHOR]

• The Zn 8 B 3 H 3 O 14 nanosheets were discovered and efficiently synthesized by the one-step coprecipitate method. • This method is simple, high yield and low cost to prepare Zn 8 B 3 H 3 O 14 nanosheets. • The nanosheets have good thermal stability, and their decomposition temperature reaches 414 °C. With the rapid development of two-dimensional materials, the exploration of new two-dimensional materials has become a research hotspot. In this work, novel Zn 8 B 3 H 3 O 14 nanosheets were efficiently synthesized by the one-step coprecipitate method using the water bath reaction at 70 °C for 24 h. The preparation of Zn 8 B 3 H 3 O 14 nanosheets by this method has the advantages of a simple preparation process, low cost, low equipment requirements, and mass production. The microstructure and morphology of nanosheets were characterized in detail. In addition, the nanosheets have good thermal stability properties, and their decomposition temperature reaches 414 °C. This allows the nanosheets to adopt higher processing and service temperatures when applied to polymer materials. [ABSTRACT FROM AUTHOR]

Abstract Graphene oxide (GO) is one of the most important ceramic-toughening candidates due to its outstanding physical and chemical properties. In this paper, nacre-like alumina ceramics reinforced with GO have been prepared by freeze casting followed by hot pressing. The experimental results showed that a laminated structure with homogeneous distribution of GO was obtained in the composites. Microstructural analysis, relative densities, flexural strength and fracture toughness of the samples were investigated to reveal the effect of GO. Higher flexural strength and fracture toughness (~380 MPa and ~7.5 MPa m1/2, respectively) were achieved and the multiple length-scale toughening mechanisms of composites contributed to the improved mechanical properties. The results show that it is a promising method to enhance the mechanical properties of nacre-like alumina by the addition of GO. [ABSTRACT FROM AUTHOR]

Abstract Bimetallic carbides with high activity and stability are promising potential materials for energy-storage application. However, the researches about Fe 2 MoC as electrode material on supercapacitors are comparatively weak, and the processing methods of Fe 2 MoC were also relatively few. Herein, a simple hydrothermal method, combining with carbothermic treatment at 900 °C, is explored to fabricate molybdenum iron carbon (Fe 2 MoC) successfully. Chitosan is not only a carbon source, but also a chelating agent to form bimetallic carbide rather than two separated monometallic carbide during the high-temperature treatment. Fe 2 MoC nanoparticles possessing large specific surface, high activity, stability and small resistance were the promising candidate for electrode material. Systematic electrochemical characterizations have verified the Fe 2 MoC (chitosan as carbon source) possesses a specific capacitance (97.7 F/g at a current density of 0.5 A/g), high rate capability (97.0% capacitance retention from 0.5 to 10 A/g) and cycling stability (83.9% capacitance retention after 1000 cycles) in 1 M KOH. In addition, it offers the energy density of 6.74 Wh/kg at a power density of 21 kW/kg. In view of the low-cost and excellent performance, Fe 2 MoC will hold great promise in energy-storage field for supercapacitors. [ABSTRACT FROM AUTHOR]

Well-dispersed boron nitride nanosheets (BNNSs) reinforced fused silica composites were successfully fabricated by surface modification assisted flocculation method. Surface modification can enhance the performance of flocculation process. BNNSs were homogeneously mixed with fused silica through the electrostatic interaction between hydroxylated BNNSs with negative charge and amino-modified fused silica with positive charge. The BNNSs can act as excellent nanofillers for enhancing the mechanical properties of fused silica composites. Approximately 74% and 48% increases in flexure strength and fracture toughness can be achieved for the 1.5 wt% BNNSs/fused silica composite, respectively. The toughening mechanisms were analyzed by microstructural characterization, especially for pull-out mechanism. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide@boron nitride nanosheet (RGO@BNNS) hybrids were prepared for the first time using template-assisted autoclave pyrolysis technique at the temperature as low as 600 °C. The developed method can be scaled into gram-scale synthesis of the material. The BNNSs combine with RGO through van der Waals interplanar interaction without damaging the structures of RGO. Such ultrathin BNNSs on the surface of RGO can serve as high-performance oxidation-resistant coatings in oxidizing atmospheres at high temperatures. The RGO@BNNS hybrids can sustain up to 800 °C over a relatively long period of time. [ABSTRACT FROM AUTHOR]

In order to overcome intrinsic brittleness and poor mechanical properties of fused silica (FS), boron nitride nanosheets (BNNSs) as a novel reinforcement were employed for fabrication of BNNSs/fused silica composites. BNNSs with micron lateral size were homogeneously dispersed with FS powder using a surfactant-free flocculation method and then consolidated by hot pressing. The flexural strength and fracture toughness of the composite with the addition of only 0.5 wt.% BNNSs increased by 53% and 32%, respectively, compared with those of pure FS. However, for higher BNNSs contents the improvement in mechanical properties was limited. Microstructural analyzes have shown that the toughening mechanisms are combinations of the pull-out, crack bridging, and crack deflection mechanisms. [ABSTRACT FROM AUTHOR]

BNNSs were prepared efficiently by magnesium borate nitridation. BNNSs/eutectic-composition Al 2 O 3 /YAG/YSZ ceramics were prepared by hot pressing sintering. The addition of BNNSs did not change the phase composition of BNNSs/eutectic-composition Al 2 O 3 /YAG/YSZ ceramics. The bending strength and fracture toughness of 1.5wt%BNNSs/ eutectic-composition Al 2 O 3 /YAG/YSZ ceramic were increased by 19.0% and 18.9% respectively. Doped BNNSs exist at the grain boundary between two or more different grains. The toughening mechanism of BNNSs contains mainly crack deflection, BNNSs pullout and BNNSs bridging. • BNNSs/eutectic-composition Al 2 O 3 /YAG/YSZ ceramics were originally prepared with excellent mechanical properties. • The toughening mechanism of BNNSs was discussed. • The effects of temperature and BNNSs doping amount on the mechanical properties of ceramics were explored. [ABSTRACT FROM AUTHOR]

In this paper, BNNSs/Al 2 O 3 composite powder was prepared by in-situ reaction using borate nitridation method and BNNSs/Al 2 O 3 composite ceramics were prepared by hot-pressing sintering. This method achieves uniform mixing of BNNSs and Al 2 O 3 ceramic matrix and reduces the introduction of impurities in the processing process. The BNNSs/Al 2 O 3 composite ceramics have excellent bending strength (549.4 MPa), fracture toughness (5.18 MPa m1/2) and hardness (21.3 GPa). The high hardness of composite ceramics is attributed to high grain boundary strength and density. The reinforcing mechanisms of ceramics include BNNSs pull-out, BNNSs bridging, crack deflection as well as the transgranular fracture and intergranular fracture of Al 2 O 3 matrix. [ABSTRACT FROM AUTHOR]

As the precursor of MXenes (2D transition metal carbides, carbon nitrides and nitrides), MAX phase materials have attracted ever-increasing attention in electrochemical applications. In this work, we have successfully hybridized a MAX phase, Ti 2 SnC, with various ratios of carbon nanofibers (CNFs) via electrospinning. The results show that the Ti 2 SnC/CNFs compounds possess a stable lithium ion storage ability as an anode material, reaching a stable specific capacity of up to 367.5 mAh·g−1 after 500 charge/discharge cycles at the current density of 1.0 A g−1, which are drastically better than some other MAX phase materials such as Ti 3 SiC 2 and Nb 2 SnC. This strategy provides a new pathway for the improvement of the electrochemical stability of MAX phase, which has a wide application prospect. • Ti 2 SnC/CNFs was successfully prepared by an electrospinning method. • CNFs retard the volume expansion of Ti 2 SnC during the charge/discharge process. • Ti 2 SnC/CNFs performed stable lithium ion capacitance (367.5 mAh·g−1 at 1.0 A g−1). [ABSTRACT FROM AUTHOR]

• The partial S-doping NiFe 2 O 4 was obtained through a facile hydrothermal method. • The d-spacing of NiFe 2 O 4 was expended caused by partial S-doping. • The impact of partial S-doping to NiFe 2 O 4 is exposed by VASP analysis. • The optimal electrode exhibited the highest specific capacitance of 284 F/g. Nickel ferrite exhibits many advantages as electrode materials in the application of supercapacitor, such as high energy capacity and excellent cycle stability. Whereas, compared with identical-metal sulfides, the specific capacitance of NiFe 2 O 4 is still insufficient. Hence, to combine the superiorities of oxides and sulfides, partial sulfur doping NiFe 2 O 4 is obtained through hydrothermal synthesis method. Analyzed by Vienna Ab-initio Simulation Package (VASP) software and high-resolution transmission electron microscopy, the lattice parameters of NiFe 2 O 4 are confirmed to be expanded by introducing sulfur atoms, which is beneficial to electrochemical performances. At a current density of 1 A/g, the specific capacitance of partial sulfur doping NiFe 2 O 4 is calculated to be 284 F/g, higher than that of the original NiFe 2 O 4 of 182.2 F/g. Moreover, a maximum energy density of 21.14 Wh/kg is achieved at a power density of 375 W/kg. This work shows that partial sulfur doping could improve the electrochemical performance of NiFe 2 O 4. To sum up, this work provides an effective way to enhance the poor electrochemical performance of oxides, greatly encouraging the application of oxides in energy storage field. [Display omitted] [ABSTRACT FROM AUTHOR]

MAX phase materials, the precursors of MXenes (2D transition metal carbides, carbon nitrides, and nitrides), have become increasingly popular in electrochemical applications. In this study, we have successfully prepared Ti 2 SnC with high lithium capacity via the in-situ formation of SnO 2. Results show that there are TiC nanowhiskers and SnO 2 inside the Ti 2 SnC MAX calcined at 800 ℃, and the initial specific capacity could reach 377 and 371 mAh·g−1 at high current densities of 400 mA·g−1 and 1.0 A·g−1, respectively. These values are higher than those of most MAX phase materials reported in previous studies, such as Ti 3 SiC 2 and Nb 2 SnC, but the stability and rate performance are inferior, which is a direction for the future. This paper provides a new pathway for the application of MAX phases in electrochemistry, which has more in-depth application prospects. ● Ti 2 SnC with in-situ formation of SnO 2 was successfully prepared by a calcination method. ● The Ti 2 SnC layered structure slows down the volume expansion of in-situ prepared SnO 2. ● This anode material performed a better specific capacitance, arriving at 377 mAh/g at the current density of 1.0 A/g. [ABSTRACT FROM AUTHOR]

Transitional metal nitrides (TMNs) are regarded as comparatively promising electrode materials for supercapacitor due to the high electronic conductivity, good corrosion resistance and special electron structure. Herein, in this work a heterostructure Co 2 N-Ni 3 N nanosheets-nanowires arrays grown on Ni foam (NF) are designed and synthesized by a simple hydrothermal reaction and nitriding treatment. The prepared Co 2 N-Ni 3 N/NF nanoarrays has a high electrical conductivity, abundant surface active sites, charge transfer channels and the synergy effect between each component, which makes it exhibit outstanding electrochemical performance. Electrochemical test results revealed that the areal capacitance of Co 2 N-Ni 3 N/NF was 2.17 F cm−2 at 1 mA cm−2 using a three-electrode system in 1 M KOH. Meanwhile, when the current density increases to 20 mA cm−2, it can still retain 62.21% of the original capacitance, suggesting a good rate capability. In addition, in two-electrode test with Co 2 N-Ni 3 N/NF as the positive electrode and activated carbon as the negative electrode, a maximum energy density of 145.65 μWh cm−2 is shown when the power density is 0.75 mW cm−2. And it has 85.90% capacitance retention after 5000 cycles. [Display omitted] • Unique Co 2 N-Ni 3 N nanoarray heterostructure was successfully synthesized. • Co 2 N-Ni 3 N/NF achieves an areal capacitance 2.17 F cm-2 at current density of 1 mA cm-2. • The Co 2 N-Ni 3 N/NF // AC exhibits good electrochemical performance in two-electrode tests. [ABSTRACT FROM AUTHOR]

Acidic oxidation method has been massively reported as an effective method to functionalize the surface of carbon nanotubes (CNTs). However, these corrosive acids are extremely dangerous. In this paper, CNTs are firstly oxidized in alkaline solution consisting of sodium hypochlorite and potassium permanganate instead of strong acids, and subsequently the mixture is neutralized by hydrogen peroxide solution to complete the secondary oxidation in the process. Experimental results indicate that more defects in CNTs are more likely to form and functional groups are successfully grafted onto CNTs after oxidation. Moreover, zeta potential result shows that the treated CNTs with negative groups have superior suspension stability. Furthermore, the treated CNTs, length of which is shorter than that of the pristine ones, are separated from each other. Meanwhile, the treated CNTs can remain as a colloidal (well dispersed) solution for 30days. [ABSTRACT FROM AUTHOR]

The layered transition metal oxides are an essential class of cathode materials in sodium-ion batteries. However, the capacity decay mechanisms of many materials at a wide voltage window are still ambiguous. Therefore, research on the intrinsic structure of materials at the electronic or atomic level is of great significance to unlock the potential of more materials. In this study, a new family of layered NaNi 0.45 Mn 0.3 Ti 0.2 M 0.05 O 2 (M = Nb/Mo/Cr) has been demonstrated to combine high specific capacity (NaNi 0.45 Mn 0.3 Ti 0.2 Cr 0.05 O 2 , 12 mA g−1, 185.7 mAh g−1, 2-4.2 V) with preferable Na+ insertion/extraction activity (1920 mA g−1, 111.2 mAh g−1). The participation of Ni2+/Ni3+ and Cr3+/Cr4+/Cr6+ in the redox reaction upon cycling significantly contributes to the superior specific capacity, and the diffusion kinetics calculation indicates that the substitution of Cr for Ni can create a more suitable path with a low energy barrier for Na+ movement, which is particularly crucial for the rate performance. Besides, the unfavorable cycling stability is affected by the distortion of the crystal structure, suggesting that the Jahn-Teller effect of Mn3+/Ni3+ and the second-order Jahn-Teller effect of Nb5+/Mo6+ (d0 transition metal) together with Cr6+ migration caused by disproportionation of Cr4+ have inescapable responsibilities. Additionally, the reversible phase transition between the O3 and P3 phases upon Na+ insertion/extraction at a wide voltage window is identified by in situ XRD measurements and verified to be the key factor of the high coulombic efficiency for NMTCr. An in-depth understanding of NMTNb and NMTMo can provide new insights for material design and exploitation. The composition-structure-property relationships behind the electrochemical performance can be comprehended profoundly by coupling the experimental verification with density functional theory calculations. • A new family of layered NaNi 0.45 Mn 0.3 Ti 0.2 M 0.05 O 2 (M = Nb/Mo/Cr) has been prepared. • The participation of Ni2+/Ni3+ and Cr3+/Cr4+/Cr6+ contributes greatly to the capacity. • The substitution of Cr provided a suitable path with low energy barrier for Na+ movement. • The Jahn-Teller effect of Mn3+/Ni3+ and second-order JT effect of Nb5+/Mo6+ are discussed. [ABSTRACT FROM AUTHOR]

An innovative and convenient method has been performed to stabilize the surface of O3-type NaNi 0.45 Mn 0.3 Ti 0.2 Zr 0.05 O 2 composited electrode by ultrathin MgO film. There are few reports on the modification on the fabricated electrode instead of the active material powder, especially by radio frequency magnetron sputtering. Besides, the surface stability and capacity retention of MgO coated cathode are superior compared to the bare one under the high rate. The protective effect could physically enhance electrochemical performance because the MgO coating has been identified strictly. Three main reasons are discovered by investigating the mechanisms. Firstly, the MgO layer suppresses the dissolution of the active material into electrolyte; this might be the origin for more stable electrode structure. Secondly, the MgO layer boosts sodium-ion and electron transport owing to its location of the deposition. Finally, the appropriate thickness of MgO can minimize transmission resistance and SEI formation. Particularly, the half-cell constructed with NaNi 0.45 Mn 0.3 Ti 0.2 Zr 0.05 O 2 –MgO cathode delivers a good rate performance (80.3 and 70.3 mA h g−1 at 1200 and 1920 mA g−1) and a long cycle life (71.6 mA h g−1 at 240 mA g−1 for 300 cycles) when sputtering time is 10 s; meanwhile, the reversible discharge capacity (140.7 mA h g−1 at 12 mA g−1) with a cut-off voltage of 2–4 V is also a considerable achievement. The work provides a broad idea to apply MgO as a protective coating. • MgO film is performed via magnetron sputtering on NaNi 0.45 Mn 0.3 Ti 0.2 Zr 0.05 O 2 electrode. • The surface stability and capacity retention of MgO coated cathode are superior at high rate. • MgO layer boosts sodium-ion and electron transport owing to its location of deposition. • The appropriate thickness of MgO can minimize transmission resistance and SEI formation. • The NaNi 0.45 Mn 0.3 Ti 0.2 Zr 0.05 O 2 –MgO cell delivers 80.3 and 70.3 mA h g−1 at 1200 and 1920 mA g−1. [ABSTRACT FROM AUTHOR]

• Based on compressive sensing and double random encryption strategy, a novel color image compression and encryption scheme is proposed. • DRPP is presented to shuffle sparse coefficient matrices of three components of plain images. • ADMMCP is produced to measure the sparse coefficients for CS. • SDRDIC is utilized to attain the diffusion of inter-intra components of color images. • The proposed encryption algorithm is highly sensitive to the plain image. Based on compressive sensing and double random encryption strategy, a novel color image compression and encryption scheme is proposed in this paper. The architecture of compression, confusion and diffusion is adopted. Firstly, the red, green and blue components of color plain image are converted to three sparse coefficient matrices by discrete wavelet transform (DWT), and then a double random position permutation (DRPP) is introduced to confuse the coefficient matrices. Subsequently, Logistic-Tent system is utilized to generate the asymptotic deterministic random measurement matrix based on chaotic system and plain image (ADMMCP), which is used to measure the coefficient matrices to obtain measurement value matrices. Moreover, simultaneous double random pixel diffusion between inter-intra components (SDRDIC) is presented to modify the elements of measurement value matrices to obtain the final cipher image. A 4-D hyperchaotic system is applied to produce chaotic sequences for confusion and diffusion, the initial conditions of the used chaotic systems are controlled by the SHA 512 hash value of plain image and external keys, such that the proposed image cryptosystem may withstand known-plaintext and chosen-plaintext attacks. Experimental results and security analyses verify the effectiveness of the proposed cipher. [ABSTRACT FROM AUTHOR]

Morphology of transition metal oxide largely affects its electrochemical energy storage properties. This also applies to its composites. In this paper, NiFe 2 O 4 /Graphene nanosheets composites (NFO/GNSs) are successfully prepared by a facile hydrothermal method. NiFe 2 O 4 (NFO) in the sample exhibits a unique nanosheet morphology, vertically arranging on the graphene nanosheets (GNSs). Microscopically, NFO nanosheets interpenetrate on the surface of graphene to form a continuous network structure. The sample exhibits excellent specific capacitance and rate performance. It is worth mentioning that the specific capacitance increases to 140% after 5000 cycles, showing superior cycle stability. This may be due to the conductive network formed by NFO nanosheets and GNSs. Excellent electrochemical performance indicates excellent application prospects of materials in supercapacitor electrodes. Image 1 • Unique NiFe 2 O 4 nanosheets structure with graphene nanosheets was successfully prepared by a hydrothermal method. • NiFe 2 O 4 nanosheets/graphene performed a better specific capacitance, arriving at 464.15 F/g at current density of 1 A/g. • The network structure formed between NiFe 2 O 4 nanosheets and graphene nanosheets provides excellent cycle performance. [ABSTRACT FROM AUTHOR]

Due to the low cost and abundance of sodium, sodium-ion batteries (SIBs) show great potential as energy storage devices. As far as the current research is concerned, cathode materials are still the bottleneck for boosting the performance of SIBs. O3-type layered NaNi 0.5 Mn 0.5 O 2 is considered as an important cathode material of SIBs, but its irreversible phase transition, poor stability in air, and sluggish kinetics usually lead to reduced capacity, poor rate performance and high cost for material storage, which largely limit the large-scale application. Herein, a remarkable O3-type layered material NaNi 0.5-x Mn 0.3 Ti 0.2 Zr x O 2 (NaNMTZ, x = 0.02, 0.05), with stable phase structure has been synthesized by the solid-phase method. The partial substitution of electrochemical inactive Ti/Zr brings about higher electronic delocalization and entropy of mixing leading to enhanced structural stability. In addition, the enlarged interlayer spacing and good conductivity contribute to better rate capability. The micro-nano structure leads to faster Na+ diffusion rates and shorter diffusion paths for both ions and electrons. Therefore, NaNi 0.45 Mn 0.3 Ti 0.2 Zr 0.05 O 2 exhibits an initial reversible capacity of 141.4 mAh g−1 with a coulombic efficiency of 98.8% and remarkable capacity retention of 70% after 200 cycles at 0.05C, presenting better electrochemistry performance than the conventional NaNi 0.5 Mn 0.5 O 2. This study provides a new angle to design high capacity cathode materials with high rate capability and cycling stability through crystal lattice modulation. Image 1 • A remarkable O3-type layered NaNi 0.45 Mn 0.3 Ti 0.2 Zr 0.05 O 2 is designed as cathode material for sodium ion batteries. • The structural stability and rate performance of NaNi 0.45 Mn 0.3 Ti 0.2 Zr 0.05 O 2 are superior. • The higher electronic delocalization and better conductivity of NaNi 0.45 Mn 0.3 Ti 0.2 Zr 0.05 O 2 are provided. • The difference value about entropy of mixing between NaNi 0.5 Mn 0.5 and NaNi 0.45 Mn 0.3 Ti 0.2 Zr 0.05 O 2 is calculated. • The enlarged interlayer spacing and micro-nano structure contribute to the high rate capability. [ABSTRACT FROM AUTHOR]

Bimetallic carbides have aroused wide attention for energy-storage applications recently. In this work, one-dimensional Fe 2 MoC/CNFs (Fe 2 MoC/C nanofibers) are successfully synthesized via a facile electrospinning method for the first time. To obtain the most integrated structure between the Fe 2 MoC nanoparticles and carbon nanofibers, we explore the optimal heating rate during the carbonization treatment. Fe 2 MoC/CNFs exhibits an integrated one-dimensional structure under 800 °C with a heating rate of 5 °C/min. As revealed in the experimental results, Fe 2 MoC/CNFs possesses a high specific surface area of 196.9 m2/g, a high specific capacitance of 347.8 F/g at the current density of 1 A/g, an excellent rate capability of 91% capacitance retention from 1 A/g to 40 A/g, and shows superior cycling stability with the capacitance retention of about 85.6% and Coulombic efficiency of about 100% after 5000 cycles. An asymmetric supercapacitor coin-cell device using Fe 2 MoC/CNFs as the positive electrode displays an energy density of 14.5 Wh/kg at a power density of 300 W/kg and an outstanding cycling life of 93% retention after 5000 cycles. The impressive electrochemical performance indicates that the Fe 2 MoC/CNFs composite is a promising material for efficient supercapacitors. Image 1 • Fe 2 MoC nanofibers can be prepared via a facile electrospinning method. • Fe 2 MoC/CNFs-5 exhibits a superior rate capability and cycle stability. • ASC coin-cell device shows a promising energy and power density. [ABSTRACT FROM AUTHOR]

Introduction: The objective of this study was to explore the gender differences of community‐dwelling patients with schizophrenia in terms of socio‐demographics, clinical characteristic and quality of life (QOL). Methods: A total of 433 community‐dwelling patients with schizophrenia were recruited in Shenzhen city, China. Data were obtained from a face‐to‐face interview with standard research questionnaire. The QOL and insight were assessed using the WHOQOL‐BREF and the Chinese version of the insight and treatment attitude questionnaire, respectively. Results: This cross‐sectional study included 206 male and 227 female patients. Male patients were more likely to be educated, employed, smoking cigarettes and drinking alcohol, and have an early age of illness onset. In contrast, female patients were more likely to be married/cohabitating and have drug side effects. There was no significant difference between genders across all QOL domain. Multiple regression analyzes showed that mental symptoms were negatively associated with all QOL domains, whereas frequency of exercise in the past year was positively associated with all QOL domains. Higher education levels, household per capita annual income in past year (≥100 000 RMB), employment status, IATQ score, drug side effects, marital status, and number of hospitalization were also significantly associated with specific QOL domains. Discussion: There was significant gender difference in socio‐demographics and clinical characteristics among community schizophrenia patients in Shenzhen city. Gender‐specific intervention measures are needed to improve the functioning and QOL in patients with schizophrenia. [ABSTRACT FROM AUTHOR]

Uniformly dispersed boron nitride nanosheets (BNNSs) reinforced silicon nitride (Si 3 N 4) composites were prepared by surface modification assisted flocculation combined with SPS sintering. In order to improve the dispersibility of the BNNSs in the composites, the liquid phase stripped BNNSs are surface functionalized by a two-step covalently modification. The amino-modified BNNSs (NH 2 -BNNSs) and Si 3 N 4 powders have opposite surface potential, mixed evenly by electrostatic interaction during flocculation. The results showed that mechanical properties of Si 3 N 4 composites were obviously enhanced by adding NH 2 -BNNSs. The fracture toughness and bending strength of Si 3 N 4 composites added 0.75 wt% NH 2 -BNNSs were increased by 34% and 28%, respectively, compared with monolithic Si 3 N 4. Toughening mechanisms are synergistic action of the torn, pull-out or bridging of BNNSs and crack deflection mechanisms with microstructural analyzes. The dielectric properties of the Si 3 N 4 ceramics are also improved after the addition of NH 2 -BNNSs. [ABSTRACT FROM AUTHOR]

Boron nitride nanosheets (BNNSs) with relatively low dielectric constant and excellent mechanical strength were employed for fabrication of BNNSs/fused silica (FS) composites. High-temperature mechanical behavior and microstructural evolution of the composites were investigated. The addition of BNNSs can improve the mechanical properties of FS efficiently, and the reinforcement from BNNSs can be preserved during the high temperature service. The flexural strength of BNNSs/FS composites exhibited anomalous gains at certain high temperature range, which can be explained by the softening of FS matrix, the heal of defect tips, and the reinforcement from BNNSs. [ABSTRACT FROM AUTHOR]

Abstract NiFe 2 O 4 (NFO) with different morphologies were successfully synthesized via a facile hydrothermal method of different precipitants. Results showed that the NFO obtained using urea as precipitant (NFO-U) formed a nanosheet shape, while the powders prepared using CH 3 COONa (NFO-C) exhibited a nanoparticle structure. Both of the two NFO showed a good crystallinity. Conclusion was reached through the results of BET and electrochemical tests that layer structure would improve the properties through a larger specific surface area. Encouragingly, the specific capacitance of NFO-U could arrive 240.9 F/g at the current density of 1 A/g. It was worth noting that the cycle performance of NFO-U was excellent, of which the specific capacitance improved to 128% after 2000 cycles. In addition, an asymmetric supercapacitor (ASC) system was constructed utilizing NFO-U as positive electrode while activated carbon (AC) as negative electrode. The two-electrode system showed a good performance with energy density of 10.15 Wh/kg at a power density of 140 W/kg. Therefore, the construction of sheet-like structures greatly improved the electrochemical performance of NiFe 2 O 4 materials. [ABSTRACT FROM AUTHOR]

How to deal with the brittleness of ceramic materials is always one of the hot topics in the field of materials science. Design of layered ceramics with textured structure is one of the effective methods to improve their fracture toughness. The introduction of additives as interlayer phases can balance fracture toughness and flexural strength. However, the research about addition of interlayer phases and their mechanisms in the layered ceramics is still limited. In this work, nacre-like alumina ceramics were successfully fabricated by freeze casting followed by hot pressing. Silicon nitride was incorporated as the interlayer phase, and the effect on the mechanical properties of the nacre-like alumina was investigated. The addition of silicon nitride was beneficial to improvement of interlayer bonding between the alumina layers due to formation of sialon phase, leading to increase of flexural strength but decease of fracture toughness. When the content of silicon nitride was 3.3 wt%, flexural strength and fracture toughness of the sample was 468 MPa and 6.2 MPa m1/2, respectively. Compared with the sample without silicon nitride, the flexural strength was enhanced significantly. Additionally, both flexural strength and fracture toughness were improved as compared the sample without any additives. This work can provide available references for design and fabrication of high-strength and high-toughness ceramics by properly tuning the layer structure and interlayer phase composition. [ABSTRACT FROM AUTHOR]