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Carbon fiber reinforced epoxy resin matrix composite is one of the most important composite materials in the world. Many researchers have conducted a lot of research on epoxy resin matrix systems in recent years, mainly to improve the problem with the short curing time of the matrix system and epoxy resin's high viscosity. The final aim is to enhance various aspects of composites' performance and optimize the production process. A new type of water dispersed epoxy resin matrix system is investigated in this paper and the target is to optimize the mechanical, thermal, and electrical performances of the composites with the water dispersed epoxy resin matrix by varying different doping particles and different resin/catalyst ratios. Through a series of experiments, it is evident that varying the ratio of resin to catalyst in the matrix system will not significantly improve the mechanical as well as thermal properties of the composites. However, increasing the amount of catalyst in the matrix system can greatly improve the electrical properties of its composite samples. In addition to this, the addition of doping particles to the matrix systems has the effect of slightly enhancing the tensile modulus, thermal conductivity, and electrical conductivity of their composites. Highlights: A new water‐dispersed epoxy resin matrix system improves processing technology.Increasing amount of catalyst in the matrix system improves electrical resistivity.Adding particles to matrix systems has a slight effect on different properties. [ABSTRACT FROM AUTHOR]

Multiferroics with compositions BiFeO3, Bi0.90Ho0.10FeO3 and BiFe0.90Ho0.10O3 have been successfully prepared by solid-state reaction method. The structural analysis of Ho-substituted BiFeO3 affirms that the compounds are crystallized under rhombohedral perovskite structure with space group $R\overline 3 c$R3¯c along with non-perovskite Bi2Fe4O9 phase. Cuboidal-shaped grains are observed in the micrographs of the Ho-substituted BiFeO3 sample with Ho at the Fe site. The changes in electrical and dielectric parameters with Ho substitution at the A-/B-site of BiFeO3 have a strong co-relation to its structural density, phase transformation and presence of Bi2Fe4O9 phase. These parameters are strongly dependent on the frequency, and its high values are obtained at low frequency because of the space charge polarization effect. The smaller values of impedance phase angles of BiFeO3, Bi0.90Ho0.10FeO3 and BiFe0.90Ho0.10O3 compounds compared to the anticipated $90^\circ$90∘ for an ideal capacitor show that these BFO-based compounds possess non-ideal capacitive/pseudocapacitive behavior. [ABSTRACT FROM AUTHOR]

This study introduces a novel strategy to enhance the high‐temperature electrical performance of the silicone elastomer (SE), while ensuring control over its thermal and mechanical properties for SiC device packaging insulation application. For the same, the ultra‐low‐content inorganic/organic SE nanocomposites are prepared and tested (at room temperature and 150°C) by grafting polyhedral oligomeric silsesquioxane (POSS) nanofillers and doping organic semiconductors. It is found that grafting POSS nanofillers enhances the SE's thermal and mechanical properties. Moreover, doping the grafted SE with different organic semiconductors (ITIC, PCBM, and NTCDA) further improves its electrical properties and charge dynamics at 150°C. The optimal doping content for ITIC, PCBM, and NTCDA is found to be 0.05, 0.10, and 0.15 wt%, respectively. Among these, NTCDA exhibits superior electrical performance at 150°C. Particularly, compared to pure SE, NTCDA doping and POSS grafting reduce the electrical conductivity by an order of magnitude and increase the breakdown strength, charge hopping activation energy, and trap energy level by 65.5%, 0.20 eV and 0.73 eV, respectively. This study finds that organic semiconductors outperform nanostructures in inhibiting electron injection and immobilizing free electrons at high temperatures. Highlights: Nano‐POSS grafting enhances material properties by reinforced molecular chains.Charge dynamics is studied by space charge and current integrated charge at HT.Organic semiconductors improve electrical properties and charge dynamics at HT.Organic semiconductors outperform nanofillers in immobilizing electrons at HT.The ideal organic semiconductor doping level correlates with its energy gap. [ABSTRACT FROM AUTHOR]

The thermal and electrical properties of photovoltaic cell (PVC) under linear phenomenological heat transfer law between it and the environment is studied through finite time thermodynamics and the volt-ampere characteristic equation. The properties of PVC are affected by heat transfer between PVC and environment. There are optimal solar radiation intensity and PVC output voltage (OV), which make the photoelectric conversion efficiency (PECE) of PVC reach the highest value. When OV and solar radiation intensity are 28.50 V and 700 W/m2, the maximum PECE is 0.156. There is also the best solar radiation intensity, which makes the open-circuit voltage (OCV) reach the maximum. When solar radiant intensity is 669 W/m2, the maximum OCV is 33.14 V. The values of power output and short-circuit current (SCC) are monotonically increasing with solar radiation intensity. Given solar radiation intensity, the power output and OV exhibit a parabolic shape. The operating temperature falls first and then grows with the OV. However, the change of operating temperature with OV is not much. Band gap is a decreasing function of operating temperature. This article can give theoretical support for the design and use of PVCs. [ABSTRACT FROM AUTHOR]

The article gives an overview of energy storage composites, their materials, manufacturing processes, and applications. Carbon- and metal-based nanoparticles and their relevant properties are presented. We focus on multifunctional structural supercapacitors and their components. Thus, we describe the main structural electrolytes and elements of the structural electrodes. We show that the nanoparticles significantly influence the electrochemical properties of the electrode. For example, carbon-based nanoparticles can achieve low energy density but high power density, while the opposite is true for metal-based nanoparticles. We show that when carbon- and metal-based nanoparticles are used together, a positive synergy is created between them, promoting the development of favorable electrochemical properties in the electrodes. Furthermore, we present structural supercapacitors and possible ways to introduce nanoparticles into the system. Finally, we present a summary of the progress achieved so far and the advancements expected in the future, as well as potential areas where structural supercapacitors could be used.

Bi 0.5 Na 0.5 TiO 3 -based ferroelectric materials with strong ferroelectricity and high Curie temperature have great application prospects in modern microdevices. In this paper, 0.92BNT-0.08BT ceramic coating was prepared by supersonic plasma spraying. The phase, microstructure, electrical properties and domain response of 0.92BNT-0.08BT ceramic coating were analyzed. The findings demonstrate that the 0.92BNT-0.08BT ceramic coating is without obvious structural defects and has a completely structure with good interface bonding. 0.92BNT-0.08BT ceramic coating has good electrical properties, the dielectric constant is 417, the dielectric loss is 0.3, and the remnant polarization is 16.6 μC/cm2. The piezoelectric force microscopy (PFM) results show that the 0.92BNT-0.08BT ceramic coating generally exhibits irregular and inhomogeneous striped nanodomains, with significant changes in amplitude and phase response under different electric fields. The results using switching spectroscopy-piezoresponse force microscopy (SS-PFM) show that the local piezoelectric coefficient (PR max) of the 0.92BNT-0.08BT ceramic coating reaches 754.3 p.m./V at a voltage of 20 V, and the ferroelectric domains exhibit a clear switching behavior. [ABSTRACT FROM AUTHOR]

Negative temperature coefficient (NTC) thermistors are key components for temperature sensors and actuators. In this work, Sn0.94-x-yAlxSmySb0.06O2+δ (0 ≤ x ≤ 0.05, 0 ≤ y ≤ 0.15) ceramics were prepared by solid-state reaction method for potential application of NTC thermistors. The Sm/Al co-doped SnO2 ceramics had the main phase with tetragonal structure as that of SnO2 crystal. The prepared ceramics presented adjustable room temperature resistivity (ρ25) and temperature sensitivity (B value) for various Al contents. Sm/Al co-doping significantly improved the ageing stability, the resistance shift rate was below 3% after ageing at 150°C for 500 h, while the average resistance shift rate was 41.4% of the ceramics without Sm-doping. The conduction mechanisms and the effect of dopants on the ageing stability were investigated by analysis of impedance spectra and element valences combined with defect chemistry theory.

ZnO-Bi2O3-Co2O3-NiO-Mn3O4-SiO2-Cr2O3 varistor ceramics were prepared by solid-phase sintering method.The effects of different doping amounts of Cr2O3 on the microstructure and electrical properties of ZnO varistor ceramics were investigated, and the phases, microstructures and electrical properties of samples were characterized. The results indicate that the addition of Cr2O3 effectively inhibits the abnormal growth of ZnO grains, enhances the uniformity of grain distribution, reduces the ZnO grain resistance and increases the grain boundary resistance.In the range of 0%-0.21% (molar fraction, the same below) of Cr2O3 addition, the nonlinear coefficient of the varistor ceramics increases first and then decreases as the addition amount increases. When the Cr2O3 doping amount is 0.14%, the ZnO varistor ceramics exhibit excellent electrical properties, with a potential gradient E1 mA=216 V·mm-1, leakage current JL=0.36 μA·cm-2, nonlinear coefficient α=25, residual voltage ratio K=1.815, and aging coefficient Kct=0.647. In addition, the initial U1 mA value of varistor ceramics still maintains 96.75% after impacted by 100 kA pulse current twice with 4/10 μs waveform. The Cr2O3 doped ZnO varistor ceramics demonstrate excellent impulse stability and significant application potential for lightning arresters of power distribution systems.

The rapid development of flexible conductive materials has promoted the research on conductive polymer (CP)‐based materials. However, CPs have relatively low thermal conductivity (TC), which can result in severe heat dissipation problems for device applications. In this work, core–sheath structured polyaniline@boron nitride (BN@PANI) composites were prepared by in‐situ growth strategy, in which PANI nanowire arrays were uniformly anchored to the surface of BN microrods. Thanks to the particular structure, the as‐prepared BN@PANI composite shows excellent thermal management capabilities. Specifically, the TC of the BN@PANI composite is 4.32 W/m·K at low BN loading of 10 wt%, which is almost 17.8 times that of pure PANI. Moreover, the excellent heat dissipation performance is intuitively presented through infrared imaging technology. Impressively, the PANI nanowire arrays are vertically arranged on the BN surface to form a conductive pathway, which results in conductivity comparable to pure PANI. This work broadens the ideas for preparing high‐performance CP‐based composites by using insulating fillers. Highlights: Core–sheath structured BN@PANI composites were prepared by an in‐situ growth strategy.The thermal conductivity of composite was 4.32 W/m·K at 10 wt% BN loading.The introduction of BN had little effect on the conductivity of PANI.The BN@PANI composites possessed excellent thermal management capability.This work contributes to understanding heat transport in conductive polymers. [ABSTRACT FROM AUTHOR]

There is a growing demand for advanced conductors with enhanced electrical properties to increase the energy efficiency in various applications. A promising strategy to achieve this involves the use of ultraconductive copper (UCC) composites that incorporate highly conductive carbon materials, such as carbon nanotubes (CNTs), into the copper matrix. In this study, we present a scalable brush coating technique to incorporate CNTs onto Cu substrates to produce Cu–CNT–Cu composites. The process involves brush coating the CNT solution on Cu tape substrates, followed by vacuum-assisted thermal removal of organic moieties (e.g., surfactant/polymer). This step ensures the creation of a uniformly distributed CNT network within the Cu matrix. By addition of a thin film Cu overlayer, the fabricated Cu–CNT–Cu composite architecture demonstrates similar electrical conductivity, increased current carrying capacity, and enhanced mechanical properties compared to pure Cu reference tapes. The performance characteristics of these UCC tapes along with the scalability of the brush coating approach hold great promise for the fabrication of advanced conductors for wide-ranging energy applications. [ABSTRACT FROM AUTHOR]

We reported the growth of (AlGa)2O3 layers on (11 2 ¯ 0), (10 1 ¯ 0), and (10 1 ¯ 2) α -Al2O3 substrates using MBE, and the electrical characterization of Si-doped (AlGa)2O3 layers. The Ga2O3 layers grown on (10 1 ¯ 0) and (10 1 ¯ 2) α -Al2O3 were α -phase single crystals, while the Ga2O3 layer grown on (11 2 ¯ 0) α -Al2O3 consisted of (11 2 ¯ 0) α -Ga2O3 and ( 2 ¯ 01) β -Ga2O3. The Al composition of the (11 2 ¯ 0) and (10 1 ¯ 0) (AlGa)2O3 layers was controlled by varying the Al flux. The Si-doped (10 1 ¯ 0) α -(Al x Ga1- x )2O3 layers with x = 0–0.41 were electrically conducting. [ABSTRACT FROM AUTHOR]

With the development of microelectronics products with high density and high power, it is urgent to improve the electrical and thermal conductivity of electronic paste to achieve the new requirements of packaging materials. In this work, a new synthesis method of Ag-MWCNTs was designed: Firstly, carboxylated MWCNTs and stannous chloride were used as raw materials to prepare high-loading-rate Sn-MWCNT composite material to ensure the high loading rate of metal on the MWCNT surface. Then, Ag-MWCNT composite material was prepared by the chemical displacement method to solve the problem of the low loading rate of silver nanoparticles on the MWCNT surface. On the basis of this innovation, we analyzed and compared the electrical, thermal, and mechanical properties of Ag-MWCNT composite electronic paste. Compared with the electronic paste without adding Ag-MWCNTs, the resistivity was reduced by 77%, the thermal conductivity was increased by 66%, and the shear strength was increased by 15%. Therefore, the addition of Ag-MWCNTs effectively improves the electrical, thermal, and mechanical properties of the paste, making it a promising and competitive choice for new packaging materials in the future. [ABSTRACT FROM AUTHOR]

Bioactive borosilicate glasses having weight composition (74-X) SiO2, 16 Na2O, 10 B2O3 and (X) V2O5 (wt%), where (X = 0, 0.1, 0.3, 0.5, 1, 2.5, 4 wt %) were synthesized using the conventional melting procedure. Bioactive glass samples were melted in a platinum crucible of 50 ml capacity at 1400 °C in the globular furnace with air as the furnace atmosphere and kept hold for 2 h. These glasses were characterised and tested by using several experiment techniques like XRD, FTIR, SEM and EDX. The bioactivity of the borosilicate samples was determined by submerging them in simulated body fluid (SBF) for different time intervals. The developed hydroxy apatite (HA) was identified by FTIR, XRD, SEM and EDX technique. The obtained results demonstrate that the in-vitro bioactivity of the samples increases with the increase in V2O5 doping in samples. Various properties like density, compressive strength and electrical properties are determined. Physical and mechanical properties are improved after V2O5 doping. Electrical properties are improved after SBF doping, and the result shows the ion movement due to increased bioactivity. The in-vitro hemocompatibility and cellular compatibility on MG-63 cell lines were carried out. It was found that samples were compatible with human blood. Cellular proliferation is increased with increasing concentration of V2O5. However beyond 0.5% V2O5 doping the value of bioactivity decreases at higher concentrations of samples in culture media. [ABSTRACT FROM AUTHOR]

To collect aged silicone rubber (SiR) insulators with different numbers of years in use, which is for developing a degradation diagnostic system of SiR, is difficult. Therefore, it is desired to make degraded SiR surface which has similar characteristics to the degraded surface in outdoor. To realize the fabrication, we characterized the surfaces of aged SiR specimens cut out from a 22 kV line post insulator used in the coastal area for 20 years. The results showed that to introduce fine particles into the surface is necessary for making degraded surface having the minute surface roughness. Additionally, it was found that to activate the dispersion of LMW with foreign matters is also necessary. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to provide guidance for the manufacturers and the related researchers of the electric shock shielding clothing, the mechanism of the electric shock shielding functional fabric was analyzed theoretically, and the key parameters to be considered in the design of the electric shock shielding functional fabric were explored. The development of the electric shock shielding clothing at home and abroad was comprehensively reviewed, including the electrical conductivity of the electric shock shielding functional fabric, and the structural design of the shielding clothing, electrical property test as well as durability and so on. The problems in the research and development of the electric shock shielding clothing were analyzed. It is proposed that in the future, the research and development of the electric shock shielding clothing should focus on high performance, lightweight, low cost, durability and green development and so on. In particular, the standard test method for its electrical property should be formed as soon as possible so as to ensure the accuracy and effectiveness of periodical check of the shielding clothing and the personal safety of the relevant workers. [ABSTRACT FROM AUTHOR]

Summary: Silicon anodes hold promise for future lithium-ion batteries (LIBs) due to their high capacity, but they face challenges such as severe volume expansion and low electrical conductivity. In this study, we present a straightforward and scalable electrostatic self-assembly method to fabricate WSi@SiOx/Ti3C2 composites for LIBs. Silicon nanosheets and the ultra-thin oxide layer SiOx serve as sufficient buffers against volume changes, while the layered MXene enhances the electrical conductivity of the composite and promoted Li+/e− transport. Additionally, cationic surfactant-treated Ti3C2 provides more active sites for WSi@SiOx attachment and acts as an intercalating agent, enabling WSi@SiOx to enter the interlayer spaces of Ti3C2. The WSi@SiOx/Ti3C2 electrodes significantly improved electrochemical performance, achieving a capacity of 1,130 mAh g−1 after 800 charge/discharge cycles at 500 mA g−1. This study not only presents a straightforward pathway for high-value utilization of silicon waste but also offers a feasible route for preparing high-performance and cost-effective silicon-based LIBs.

High-performance Cu/Graphene composite wire synergistically strengthened by nano Cr 3 C 2 phase was directly synthesized via hot press sintering followed by severe cold plastic deformation, using liquid paraffin and CuCr alloy powder as the raw materials. Since graphene is in situ formed under the catalysis of copper powder during the sintering process, the problem that graphene is easy to agglomerate and difficult to disperse uniformly in the copper matrix has been solved. The nano Cr 3 C 2 -particles nailed at the interface favor to improve the interface bonding. The Cu/Graphene composite possesses high electrical conductivity, hardness, and plasticity. The composite wire exhibits high electrical conductivity of 96.93% IACS, great tensile strength of 488 MPa, and excellent resistance to softening. Even after annealing at 400°C for 1 h, the tensile strength can still reach 268 MPa with a conductivity of about 99.14% IACS. The wire's temperature coefficient of resistance (TCR) is largely reduced to 0.0035/°C due to the complex structure, which leads the wire to present low resistivity at higher temperatures. Such Cu/Graphene composite wire with excellent comprehensive performance has a good application prospect in high-power density motors.

editorial

Not only can perovskite solar cells be exposed to high temperatures, up to 80 °C, depending on the operating environment, but absorbed energy is lost as heat, so it is important to have thermal stability for commercialization. However, in the case of the recently reported p-i-n structure solar cell, most of the electron and hole transport layers are composed of organic materials vulnerable to heat transfer, so the light absorption layer may be continuously exposed to high temperatures when the solar cell is operated. In this study, we attempted to improve the thermal conductivity of the electron transport layer using phenyl-C61-butyric acid methyl ester (PCBM) containing zinc oxide (ZnO). As a result, the thermal conductivity was improved by more than 7.4% and 23.5% by adding 6.57vol% and 22.38vol% of ZnO to PCBM, respectively. In addition, the insertion of ZnO resulted in changes in the electron transport behavior and energy level of the electron transport layer. As a result, it was confirmed that not only could the temperature stability of the perovskite thin film be improved, but the efficiency of the solar cell could also be improved from 14.12% to 17.97%. [ABSTRACT FROM AUTHOR]

In this paper, we report the structural and electrical properties of TiZrN thin films deposited by dc-magnetron sputtering under a working pressure of 0.67 Pa at room temperature. The phase structure, crystallinity, morphology, electrical properties, and hydrophilicity of TiZrN films were found to be strongly dependent on the nitrogen gas ratio of N2/(Ar+N2). In vitro Baby hamster kidney (BHK) cell adhesion on the TiZrN films was also tested for primary biocompatibility evaluation. The sputtered films exhibit a single-phase structure of (Ti, Zr)Nx without the presence of secondary phases such as TiNx or ZrNx. The lowest surface resistivity and resistivity values are observed in the films deposited at a 10% nitrogen ratio, with values of 12 Ω/□ and 1.79 × 10−5 Ω.m, respectively. TiZrN films deposited at different nitrogen ratios between 3–30% show hydrophilic properties, with contact angles ranging from 60 to 83 degrees. In vitro BHK cell test indicated that TiZrN films possess excellent biocompatibility. With the interesting performances indicated, TiZrN films have great potential for electrode applications and biomedical implants. [ABSTRACT FROM AUTHOR]

The present work reports fabrication of polyaniline (PANI)-porous silicon (PS) heterostructure obtained by PANI coating on PS using vacuum coating deposition technique. Electrical properties are studied through the measurement of current (I)–voltage (V) characteristics. Some parameters (viz. ideality factor, barrier height, series resistance) are calculated from the I-V plots. Fitting of these curves is done with the thermionic emission (TE) and Cheung's method. It is found that Cheung's method provides better knowledge about the heterostructure in terms of series resistance. The heterostructure comes out as an electrically active material with minimal series resistance of 23.53 kΩ resulting high-driven electric current. The I–V of the heterostructure follows space charge limited conduction (SCLC) mechanism due to the presence of traps or imperfection in the heterostructure. Prior to electrical measurement the device is characterized through field emission scanning electron microscope (FESEM), UV–vis–NIR reflectance, photoluminescence (PL) and Raman spectra for morphological and optical properties. FESEM shows the modified PS structure after PANI deposition revealing short-chained PANI molecules due to thermal treatment. UV–vis-NIR shows lower reflectance of the heterostructure due to impregnation of PANI to the pores of PS resulting change in refractive index. PANI-PS shows quenched PL peak. Raman spectra complement the FESEM results. [ABSTRACT FROM AUTHOR]

Ultraviolet light (UV) irradiation crosslinked linear low‐density polyethylene (LLDPE)/ethylene propylene diene monomer (EPDM) composites with different blending ratios were prepared using benzophenone (BP) as photoinitiator and triallyl isocyanurate (TAIC) as crosslinking agent. The irradiation time was determined, the effects of rubber‐plastic ratio on the crystallization behaviors, mechanical properties, crosslinking properties and electrical properties of LLDPE/EPDM composites were investigated. The results show that with the increase of EPDM content, the crystalline structure of LLDPE/EPDM composite become looser and the crystallinity decreased. The blending of EPDM and LLDPE results in two different aggregation states of the same crystalline form. With the increase of LLDPE content, the crosslinking efficiency, tensile strength, and energy storage modulus show a significant upward trend. When two polymers simultaneously exist in the material, if the difference between the contents of two polymers is large, the breakdown strength of the composite is relatively lower. The relaxation polarization of LLDPE/EPDM at low frequencies increases with the content of EPDM, thus leading to the increase of loss factor at low frequencies. A novel UV crosslinked modified EPDM insulating material with high production efficiency and improved insulation performances has been developed for use as an insulating layer for flexible power cables. [ABSTRACT FROM AUTHOR]

Binary blends of unsaturated polyester (70%) and nitrile rubber (NR) (30%) and their composites are prepared. Zinc oxide nanoparticles (ZnONPs) were used as a filler in the hand-lay method. ZnONP weight ratios ranged from 0 to 3 wt.%. The ZnONPs were characterised using techniques such as X-ray diffraction (XRD) and scanning electron microscopy (SEM) to examine their crystalline structure and shape. The thermal and dielectric properties of the samples were examined as a function of filler content. Additionally, the theoretical and experimental densities of the nanocomposites were examined using the mixing rule and Archimedes’ principle, respectively. The thermal conductivity and diffusivity values exhibited variations between increasing and decreasing trends as the filler concentrations increased. Among all samples tested, the one containing 2.5% ZnONPs demonstrated the highest thermal conductivity and the lowest diffusivity when compared to the pure blend. As the ZnONP weight ratio increased, the corresponding dielectric constant value rose linearly, while the resistivity decreased linearly. Thermogravimetric analysis (TGA) revealed a significant improvement in the level of char yield and thermal stability of nanocomposites with increasing ZnONP concentration in the matrix. [ABSTRACT FROM AUTHOR]

The pulsed laser deposition (PLD) technique for the preparation of Ba0.85Ca0.15Zr0.1Ti0.9O3 (BCZT) epitaxial films usually requires high deposition temperature and is prone to contain oxygen vacancy defects. In order to provide a post-annealing treatment process based on PLD, high-quality BCZT epitaxial films were successfully prepared on conductive substrates, and the effects of annealing temperature on the structure and properties of BCZT epitaxial films were investigated. The films annealed at different temperatures of 750, 800, 850 and 900 °C show pure phases. The ferroelectric properties of the films are gradually improved as the annealing temperature increase, with 2Pr increasing from 4. 2 to 17. 6 μC/cm². However, the sample at the annealing temperature of 900 °C has the most serious leakage current problem. By fitting the J-E relationship, it is found that the films annealed from 700 °C to 850 °C follow the Ohmic conduction mechanism at low fields, while the samples annealed at 900 °C follow the space charge limited current mechanism, and all the films follow the Fowler- Nordheim tunneling mechanism at high fields. [ABSTRACT FROM AUTHOR]

PN junction with p-Si / n-Ga2O3 structure was developed by metal organic chemical vapor deposition (MOCVD) technology on p-type Si (111) substrate. The crystal structure, surface morphology and surface roughness were measured by X-ray diffractometer and atomic force microscope. Then Ti / Au electrodes on these samples were developed by magnet sputtering and evaporation for testing the PN junction characteristics such as I-V curve chart, threshold voltage, on-off current ratio, reverse saturation current, ideal factor, and the barrier height at zero bias voltage. The regulation of PN junction characteristics with growing parameters such as doping concentration and film thickness was studied, and the reasons were given. The crystal quality of β-Ga2O3 thin film and the characteristics of the devices were improved by two-step growing method. A set of PN junction samples were fabricated at three different temperatures when the buffer was developed. Finally, the best conditions of fabricating the PN junction devices was found, and the lattice mismatch and thermal mismatch between Si substrate and β-Ga2O3 thin film were reduced. A high quality n-type β-Ga2O3 thin film with surface roughness of 4. 21 nm and a PN junction with low ideal factor of 42. 1 was obtained. [ABSTRACT FROM AUTHOR]

Dy-doped (Ba0.85Ca0.15)(Zr0.1Ti0.9)O3 ([(Ba0.85Ca0.15)0.99Dy0.01](Zr0.1Ti0.9)O3, 0.01Dy-BCZT) lead-free multifunctional ceramics were prepared by conventional solid-state sintering method, in which the effects of ceramic processing conditions were studied by structural analysis and performance characterization. The sintered 0.01Dy-BCZT ceramics have pure perovskite phase with composition near morphotropic phase boundary alongside apparent tetragonal distortion, high density and densified micro-morphology obtained via tailoring calcination and sintering temperatures. High resistivity, excellent dielectric performance and piezoelectricity were acquired, which were affected greatly by ceramic processing conditions. All samples exhibit excellent ferroelectric and strain properties, which approach intrinsic physical performance and have little dependency on ceramic processing conditions. Appearance of a strong broad emission peak, centred at ∼442 nm, is related to the 4F9/2 → 6H15/2 electron transition. Strong piezoelectric-fluorescent coupling effect was produced due to adding Dy and using BCZT piezoelectric matrix, which provides a promising choice in optoelectronic application field.

In recent years, solid polymer electrolytes (SPE) has attracted much attention because of its good safety and environmental stability, among which poly(ε-caprolactone) (PCL) based solid electrolyte film is one of the most potential materials. We have adopted the method of synthesizing polymer nanocomposites with natural clay, which can effectively meet the needs of electrolytes. In this study, cetyl trimethyl ammonium bromide (CTAB) was used to modify rectorite (REC), and the ε-CL monomer is inserted between the rectorite silicate layers. PCL/organic rectorite (OREC) nanocomposites were synthesized by in situ intercalation polymerization. The yield of the polymer nanocomposite could reach 93.6% when the molecular weight of the polymer nanocomposite was 39 000. The effects of OREC addition on the morphology, thermal stability, and electrochemical properties of PCL/OREC nanocomposites were investigated by various characterization methods. The temperature can be increased by 50 °C when the thermal decomposition is 50 wt%, and the crystallinity decreases by 4.6%. Composite polymerelectrolytes (CPEs) (PCL/OREC) showed a good electrical conductivity of 1.13·10–4 S·cm–1 at 60 °C and an excellent capacity retention rate of 96.7% after 100 cycles at 0.5 C current density. This study has important guiding significance for the development of polymer nanocomposites as solid electrolytes.

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Insulation materials are ubiquitous in industrial production and daily life. Due to the huge uncertainties of their working environments, insulation materials are easily damaged and difficult to maintain during the use. The research of selfhealing materials has received much attention in recent years. The development of insulation materials with self-healing function can not only save the economic damage caused by failure and repair, but also protect people ’s lives. Different applications of self-healing insulation materials are reviewed, and research on the application of self-healing technologies such as microcapsules and dynamic bonds in the field of insulation materials are described. The structure and properties of self-healing insulation materials are analyzed, and the advantages and disadvantages of various self-healing insulation materials are summarized, thus providing new ideas and directions for the further applications of self-healing insulation materials. In addition, in order to realize the intelligent development of self-healing insulation materials, the research progress of new self-healing materials that can provide direction for the further development of self-healing insulation materials are also reported, mainly from the perspectives of excellent dynamic properties and multiple dynamic properties, to further expand the research field of self-healing insulation materials. The development prospect and direction of self-healing insulation materials in the future are prospected. It could serve as a guide for the further developments in materials science. [ABSTRACT FROM AUTHOR]

In this paper, the interactions between the transverse loads and the electrical field quantities are investigated based on the nonlinear constitutive relation. By considering a composite beam consisting of a piezoelectric semiconductor and elastic layers, the nonlinear model is established based on the phenomenological theory and Euler's beam theory. Furthermore, an iteration procedure based on the differential quadrature method (DQM) is developed to solve the nonlinear governing equations. Before analysis, the convergence and correctness are surveyed. It is found that the convergence of the proposed iteration is fast. Then, the transverse pressure induced electrical field quantities are investigated in detail. From the calculated results, it can be found that the consideration of nonlinear constitutive relation is necessary for a beam undergoing a large load. Compared with the linear results, the consideration of the nonlinear constitutive relation breaks the symmetry for the electric potential, the electric field, and the perturbation carrier density, and has little influence on the electric displacement. Furthermore, the non-uniform pressures are considered. The results show that the distributions of the electric field quantities are sensitively altered. It indicates that the electrical properties can be manipulated with the design of different transverse loads. The conclusions in this paper could be the guidance on designing and manufacturing electronic devices accurately. [ABSTRACT FROM AUTHOR]

Extensive research has focused on enhancing the energy storage density of polypropylene (PP) to meet the demands of high-power and compact electronic devices and electrical systems. However, there is a lack of studies addressing the delicate balance between energy storage density and dielectric loss. Dielectric loss can lead to excessive heat generation, posing a threat to the operation of energy storage capacitors. In this study, PP grafted with glycidyl methacrylate (GMA) was used as a compatibilizer and incorporated into a PP/nano ZrO2 blend to form a ternary system of PP/nano ZrO2/PP grafted GMA. A comparative study was conducted to analyze the effects of GMA grafting and individual doping of nano ZrO2 on the dielectric performance of PP. The results demonstrate that the ternary system not only ensures a high breakdown voltage (382.29 MV/m) but also possesses a high dielectric constant (2.67), thereby achieving an energy storage density of 1.7275 J/cm3 while maintaining low dielectric loss. Furthermore, grafting GMA introduces a significant number of deep traps, a phenomenon substantiated by the results of thermal stimulated depolarization current tests and molecular simulation calculations. However, the ternary system partially avoids the introduction of excessive deep traps associated with GMA grafting. This ternary system exhibits excellent energy storage performance, ease of fabrication, and stability, thereby enriching the research on polymer-based high-energy density dielectric materials. [ABSTRACT FROM AUTHOR]

Sr(1–x)LaxTiO3 (SLTO) nanopowder (x = 0, 0.01, 0.05, 0.07, and 0.10) were effectively synthesised by the sol-gel auto-combustion process. Bulk ceramics samples were produced by spark plasma sintering (SPS) in an Ar atmosphere. The XRD pattern of the undoped SLTO nanopowder showed the pure phase and the impurity phase (TiO2) was detected in the La-doped SLTO samples. However, the impurity phase disappeared after producing the bulk samples with the SPS process. All the samples exhibited a negative Seebeck coefficient (S). The electrical conductivity (σ) and negative Sof all the SLTO samples increased with increasing temperature and reached a maximum value at 800 K. The thermal conductivity (κ) decreased with increasing temperature and increasing La content. The SLTO with x = 0.01 showed the largest σ, negative S, power factor (S2σ) and dimensionless figure of merit (ZT) at 800 K. [ABSTRACT FROM AUTHOR]

Floating catalysis chemical vapor deposition (FCCVD) direct spinning process is an attractive method for fabrication of carbon nanotube fibers (CNTFs). However, the intrinsic structural defects, such as entanglement of the constituent carbon nanotubes (CNTs) and inter-tube gaps within the FCCVD CNTFs, hinder the enhancement of mechanical/electrical properties and the realization of practical applications of CNTFs. Therefore, achieving a comprehensive reassembly of CNTFs with both high alignment and dense packing is particularly crucial. Herein, an efficient reinforcing strategy for FCCVD CNTFs was developed, involving chlorosulfonic acid-assisted wet stretching for CNT realigning and mechanical rolling for densification. To reveal the intrinsic relationship between the microstructure and the mechanical/electrical properties of CNTFs, the microstructure evolution of the CNTFs was characterized by cross-sectional scanning electron microscopy (SEM), wide angle X-ray scattering (WAXS), polarized Raman spectroscopy and Brunauer–Emmett–Teller (BET) analysis. The results demonstrate that this strategy can improve the CNT alignment and eliminate the inter-tube voids in the CNTFs, which will lead to the decrease of mean distance between CNTs and increase of inter-tube contact area, resulting in the enhanced inter-tube van der Waals interactions. These microstructural evolutions are beneficial to the load transfer and electron transport between CNTs, and are the main cause of the significant enhancement of mechanical and electrical properties of the CNTFs. Specifically, the tensile strength, elastic modulus and electrical conductivity of the high-performance CNTFs are 7.67 GPa, 230 GPa and 4.36 × 106 S/m, respectively. It paves the way for further applications of CNTFs in high-end functional composites. [ABSTRACT FROM AUTHOR]

β-Ga2O3 nanostructures are attractive wide-band-gap semiconductor materials as they exhibit promising photoelectric properties and potential applications. Despite the extensive efforts on β-Ga2O3 nanowires, investigations into β-Ga2O3 nanotubes are rare since the tubular structures are hard to synthesize. In this paper, we report a facile method for fabricating β-Ga2O3 nanotubes using pre-synthesized GaSb nanowires as sacrificial templates. Through a two-step heating-treatment strategy, the GaSb nanowires are partially oxidized to form β-Ga2O3 shells, and then, the residual inner parts are removed subsequently in vacuum conditions, yielding delicate hollow β-Ga2O3 nanotubes. The length, diameter, and thickness of the nanotubes can be customized by using different GaSb nanowires and heating parameters. In situ transmission electron microscopic heating experiments are performed to reveal the transformation dynamics of the β-Ga2O3 nanotubes, while the Kirkendall effect and the sublimation process are found to be critical. Moreover, photoelectric tests are carried out on the obtained β-Ga2O3 nanotubes. A photoresponsivity of ~25.9 A/W and a detectivity of ~5.6 × 1011 Jones have been achieved with a single-β-Ga2O3-nanotube device under an excitation wavelength of 254 nm. [ABSTRACT FROM AUTHOR]

Ni-Zn ferrites have important applications in the field of soft magnetic materials due to their excellent magnetic properties, but their high bulk density hinders their widespread use. CNT/nickel-zinc ferrite (CNT/Ni0.5Zn0.5Fe2O4) nanocomposites was prepared by sol-gel method, and sintered at 1000 °C to be used as an electromagnetic wave absorber. The results showed that the morphology, impedance matching, density, electrical conductivity and absorption coefficient of CNT/Ni-Zn ferrite was controlled by the additional CNT content. The NZ3 sample containing 0.06 g of CNT showed high conductivity, and high absorption coefficient. The amount of 0.06 g of CNT was a critical amount for the CNT/Ni-Zn ferrite nanocomposites. Above this value, the increasing trend toward improved nanocomposite properties due to the agglomeration of CNTs was reversed. The absorption performance of the CNT/Ni-Zn ferrite nanocomposites are attributed to the incorporation of dielectric and magnetic loss mechanisms in which the magnetic portion is comparable to the dielectric portion. Possessing excellent magnetic and absorption properties, it has the potential to be an excellent electromagnetic wave absorbing material. [ABSTRACT FROM AUTHOR]

Temperature and magnetic field–dependent electrical and magnetic properties of La1−xCaxMnO3 (x = 0.4, 0.5) polycrystalline materials prepared by the sol-gel method are studied. An apically compressed/elongated-type distorted orthorhombic pnma-O′–phase crystallization occurs in the sample with the addition of Ca. The crystallized phases are ensured by the Rietveld refinement using the Fullprof package. Dangling bonds on the surfaces of the nanosized particles affect the vibrational features. Field emission scanning electron microscopy (FESEM) images depict the agglomeration of uniformly sized grains. With increase of Ca concentration, super-exchange (SE) interactions overcome the dominant double-exchange (DE) interactions and shift the Curie-temperature to a lower value (TC = 267 – 234K). Based on the Banerjee's criterion, the Arrott plot confirms a second-order magnetic phase transition in the samples. Temperature-dependent evolution of the Griffiths-like phase (GP) is observed in the samples and GP% increases with Ca content. The various transitions in the different temperature ranges and magnetic field–dependent electrical transport behaviours are explained using different theoretical models. The dopant concentration influences the Mn3+/Mn4+ ratio, leading to changes in the conductivity, which is mediated by ferromagnetically (FM) ordered conduction channels, altering the metal to insulator (M-I) as well as the ferromagnetic to paramagnetic (FM-PM) as well as the ferromagnetic to antiferromagnetic (FM-AFM) transition temperatures. The electrical transport in the high temperature region is explained using variable range and small polaron hopping (VRH and SPH) models. Using Holstein's relation, it is evident that non-adiabatic SPH (NASPH) model is the most adequate method to explain the high-temperature electrical conductivity. The half-doped samples show a higher value (~ 95%) of magnetoresistance (MR). The present study shows an increase in the Tc and TM − I towards room temperature and in the MR percentage, which may be good for different applications. [ABSTRACT FROM AUTHOR]

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Transparent conductive films (TCFs) are crucial components of solar cells. In this study, F, Cl, and Ga co-doped ZnO (FCGZO) TCFs were deposited onto a glass substrate using the sol-gel spin-coating method and rapid thermal annealing. The effects of F-doping content on the structural, morphological, electrical, and optical properties of FCGZO films were examined by XRD, TEM, FE-SEM, PL spectroscopy, XPS, Hall effects testing, and UV–vis–NIR spectroscopy. All prepared ZnO films exhibited a hexagonal wurtzite structure and preferentially grew along the c axis perpendicular to the substrate. Changes in the doping concentration of F changed the interplanar crystal spacing and O vacancies in the film. At a doping ratio of 2% (in mole), the F, Cl, and Ga co-doped ZnO film exhibited the best photoelectric performance, with a carrier concentration of 2.62 × 1020 cm−3, mobility of 14.56 cm2/(V·s), and resistivity of 1.64 × 10−3 Ω·cm. The average transmittance (AT) in the 380–1 600 nm region nearly 90% with air as the reference, and the optical band gap was 3.52 eV.

With the development of microelectronics products with high density and high power, it is urgent to improve the electrical and thermal conductivity of electronic paste to achieve the new requirements of packaging materials. In this work, a new synthesis method of Ag-MWCNTs was designed: Firstly, carboxylated MWCNTs and stannous chloride were used as raw materials to prepare high-loading-rate Sn-MWCNT composite material to ensure the high loading rate of metal on the MWCNT surface. Then, Ag-MWCNT composite material was prepared by the chemical displacement method to solve the problem of the low loading rate of silver nanoparticles on the MWCNT surface. On the basis of this innovation, we analyzed and compared the electrical, thermal, and mechanical properties of Ag-MWCNT composite electronic paste. Compared with the electronic paste without adding Ag-MWCNTs, the resistivity was reduced by 77%, the thermal conductivity was increased by 66%, and the shear strength was increased by 15%. Therefore, the addition of Ag-MWCNTs effectively improves the electrical, thermal, and mechanical properties of the paste, making it a promising and competitive choice for new packaging materials in the future.

In this work, TaC ceramics with a high density (98.6 %) and fine grains (1.42 µm) were fabricated by high pressure sintering. The as-sintered specimen possessed a high dislocation density of 1.9 × 1014 m−2, which contributed to its high hardness of 16.26 GPa. In addition, the electrical conductivity was improved. The characterization results showed that high pressure greatly promoted densification and limited grain growth. The process provides valuable experiences and ideas for obtaining other fully dense structural ceramics with fine grains. [ABSTRACT FROM AUTHOR]