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Aqueous zinc‐bromine batteries represent a promising large‐scale energy storage system, yet generally suffer from the dissolution of polybromides in the cathode. Currently, various nonpolar carbon materials are employed as hosts for the bromine cathode. Still, they typically exhibit weak adsorption capabilities toward polybromides. Here, a highly conductive Ti2CTx MXene synthesized through an eco‐friendly molten salt method is reported, serving as an ideal bromine cathode host material for the first time. Ti2CTx MXene shows strong chemisorptive capability to soluble polybromide species and can effectively immobilize them for enhanced coulombic efficiency and prolong cycling life of zinc‐bromine batteries. Additionally, Ti2CTx MXene enhances the reaction kinetics of the bromine cathode. Benefiting from the synergistic polybromide adsorption and catalysis effects of Ti2CTx, the dual‐plating zinc‐bromine batteries exhibit good cycle stability, with a capacity retention of 87% after 3000 cycles, outperforming traditional carbon host which fail after 2300 cycles. Meanwhile, Ti2CTx achieves a much lower polarization voltage of only 84 mV, significantly less than 240 mV observed with carbon hosts. This research highlights the potential of developing host materials with polybromide chemisorptive properties to advance the performance of zinc‐bromine batteries. [ABSTRACT FROM AUTHOR]

The failure mechanisms caused by electrostatic discharge (ESD) effects at ambient temperatures ranging from −75 to 125°C are investigated by Silvaco TCAD simulator. The devices are NMOS transistors fabricated with 28 nm fully depleted silicon‐on‐insulator (FDSOI) technology. Results indicate that with an increase in temperature, the first breakdown voltage of the device decreased by 27.32%, while the holding voltage decreased by approximately 8.49%. The total current density, lattice temperature, potential, and so forth were extracted for a detailed insight into the failure process. These findings provide valuable references for the design and development of ESD protection devices applied at different temperature ranges. [ABSTRACT FROM AUTHOR]

Herein, the magnetic properties and elastocaloric effects of Cu70Al19 + 0.5xMn11−0.5x (x = 0, 1, 2, 3) alloys are investigated. The resistance versus temperature curves indicate that the phase transition temperature increases as the Mn content decreases. In particular, the Cu70Al20.5Mn9.5 alloy exhibits a phase transition temperature close to room temperature. Therefore, the elastocaloric effects of this alloy are examined under stresses ranging from 200 to 500 MPa. The results show that the adiabatic temperature change of the alloy under a stress of 500 MPa reaches 9.8 K. Furthermore, the magnetization curves at 300 K reveal that the magnetic properties of the alloy significantly improve after undergoing low‐temperature aging treatment. The X‐ray diffraction patterns show that this improvement can be attributed to the transformation of the β1 phase to the ferromagnetic phase β3. Overall, the Cu70Al20.5Mn9.5 alloy demonstrates elastocaloric and magnetic properties comparable to those observed in certain Ni–Mn‐based alloys. [ABSTRACT FROM AUTHOR]

The effect of hydrostatic pressure on the martensitic transformation and magnetocaloric properties of MnNi0.88GeV0.12 alloy is studied in detail. X‐ray diffraction at room temperature shows that the alloy has a single hexagonal Ni2In‐type structure. The phase transition temperature moves to the low‐temperature region with the increase in hydrostatic pressure. Under the external magnetic field of 15 kOe, the hydrostatic pressure driving rates dTM/dP and dTA/dP are 60.25 and 65.25 K GPa−1, respectively, which indicate that the applied pressure expands the working temperature range of magnetic refrigeration. A magnetic entropy change ΔS of −4.8 J kg−1 K−1 is obtained in the external magnetic field of 15 kOe under ambient pressure. The peak value of |ΔS| is increased to 5.6 J kg−1 K−1 under hydrostatic pressure, which is closely related to the structural change of the alloy. [ABSTRACT FROM AUTHOR]

Herein, 1‐MeV electron irradiation is conducted to the AlGaInP (1.89 eV)/AlInGaAs (1.45 eV)/InGaAs (1.14 eV)/Ge (0.67 eV) upright metamorphic four‐junction (UMM4J) solar cell and its upper three key subcells. Light IV (LIV), external quantum efficiency (EQE), and deep level transient spectroscopy (DLTS) measurements are implemented to analyze the degradation of electric properties and evolution of defects of the UMM4J solar cell. The LIV results illustrate that the short circuit current (Isc), open circuit voltage (Voc), and maximum power (Pmax) degrade as a function of the logarithmic change of the electron fluence. EQE curves confirm the excellent anti‐irradiation characteristic of the AlGaInP (1.89 eV) subcell. Three types of electron traps E1 (Ec–0.16 eV), E2 (Ec–0.47 eV), and E3 (Ec–0.55 eV) are detected in the AlGaInP subcell. Two types of hole traps H1 (Ev + 0.35 eV) and H2 (Ev + 0.70 eV) are discovered in the AlInGaAs subcell and two types of hole traps H3 (Ev + 0.05 eV) and H4 (Ev + 0.36 eV) are observed in the InGaAs subcell. Nonionizing energy loss (NIEL) of 1‐MeV electrons in are calculated via Screened Relativist method. The defect concentrations show an approximately linear relationship with the displacement dose. [ABSTRACT FROM AUTHOR]

The present work based on the first principle and molecular dynamics calculations predicts the new 2D monolayers exfoliated from α‐AlxGa2−xO3 with non‐van der Waals interactions. The huge differences in electronic, optical, and thermal performances have been observed between the new 2D monolayers and their bulk parents, and these properties can effectively be tuned by the ratio of Al and Ga. In particular, the thermal conductivity of monolayer α‐AlGaO3 is the highest among the 2D α‐AlxGa2−xO3 phases. This calculation can be the basis for seeking the 2D α‐AlxGa2−xO3 with machinability, suitable optical, and thermal performances during the design and development of flexible devices. [ABSTRACT FROM AUTHOR]

The mechanical properties of low-density polyethylene/multiwalled carbon nanotubes (LDPE/MWCNTs) composites without and with 170 keV proton irradiation were studied by tensile tests. Mechanisms of changes of mechanical properties were examined by means of small angle X-ray scattering (SAXS), wide angle X-ray diffraction (WAXD), Raman spectroscopy, and scanning electron microscopy (SEM). The tensile curve of LDPE exhibits three characteristic regions, while those for LDPE/MWCNTs composites only give the first and the second ones. The tensile curves of all samples with 170 keV proton irradiation have no obvious yield phenomenon. The addition of MWCNTs increases the ultimate tensile strength and decreases the elongation at break. Moreover, the ultimate tensile strengths of both LDPE and LDPE/MWCNTs composites with 170 keV proton irradiation are enhanced, and the elongations at break for them are decreased. Based on the analyses of SAXS, WAXD, Raman spectroscopy, and SEM, both the loading of MWCNTs and the proton irradiation can change the mechanical properties of LDPE/MWCNTs composites by a number of factors including the homogeneous distribution of MWCNTs in LDPE matrix, the aberrance zone between MWCNTs, and LDPE matrix, the interaction between MWCNTs and LDPE matrix, and the crystallinities of samples. POLYM. COMPOS., 36:278-286, 2015. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

To address the issue of heat dissipation caused by the high output power density of gallium nitride (GaN) devices, using diamond‐integrated devices is an effective solution. Recent studies have suggested that incorporating a dielectric layer, such as silicon nitride (SiNx), between diamond and GaN can improve adhesion while also reducing thermal boundary resistance (TBR). In this study, plasma‐enhanced chemical vapor deposition (CVD), low‐pressure CVD, and metal‐organic CVD (MOCVD) techniques are utilized to grow the SiNx layer. The interface behavior of diamond/SiNx/GaN is analyzed through scanning electron microscopy, transmission electron microscopy (TEM), scanning TEM, and energy‐dispersive X‐ray spectroscopy, while time‐domain thermoreflectance measurement is used to characterize thermal properties. After analyzing the impact of the growth dielectric layer on the interface thermal resistance of the three growth modes, it is concluded that the dielectric layer produced by the MOCVD technique exhibits a smoother surface and lower TBR compared to the other two methods. Therefore, the use of the MOCVD technique is recommended to achieve optimal thermal performance in diamond/SiNx/GaN systems. [ABSTRACT FROM AUTHOR]