Progress in high-performance computing demands significant advances in memory technology. Among novel memory technologies that promise efficient device operation on a sub-ns timescale, resistance switching between cha...
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Despite recent advances in active metaoptics, efficient wide dynamic range combined with highspeed reconfigurable solutions is still elusive. Phase-change materials (PCMs) offer a compelling platform for metasurface o...
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Redox flow batteries (RFBs) are among the most promising grid-scale energy storage technologies. However, the development of RFBs with high round-trip efficiency, high rate capability, and long cycle life for practica...
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Redox flow batteries (RFBs) are among the most promising grid-scale energy storage technologies. However, the development of RFBs with high round-trip efficiency, high rate capability, and long cycle life for practical applications is highly restricted by the lack of appropriate ion-conducting membranes. Promising RFB membranes should separate positive and negative species completely and conduct balancing ions smoothly. Specific systems must meet additional requirements, such as high chemical stability in corrosive electrolytes, good resistance to organic solvents in nonaqueous systems, and excellent mechanical strength and flexibility. These rigorous requirements put high demands on the membrane design, essentially the chemistry and microstructure associated with ion transport channels. In this Review, we summarize the design rationale of recently reported RFB membranes at the molecular level, with an emphasis on new chemistry, novel microstructures, and innovative fabrication strategies. Future challenges and potential research opportunities within this field are also discussed.
In the automotive field, most of the manufacturers are looking to replace the material steel, aluminium with lightweight material like carbon fiber or glass fiber composite. The purpose are due to their relatively hig...
In the automotive field, most of the manufacturers are looking to replace the material steel, aluminium with lightweight material like carbon fiber or glass fiber composite. The purpose are due to their relatively high strength, higher chemical resistance, flexible usage temperature and higher stiffness than steel. In this study, mechanical properties of carbon fiber and glass fiber reinforced polymer were investigate. It was find that the tensile strength of carbon fiber composite is approximately 11% higher than that of glass fiber, almost twice in Young's modulus than that of glass fiber. Carbon fiber is two times higher than glass fiber in both flexural stress and young modulus of flexural three points bending test. Image analysis of fracture and damage were detect by field emission scanning electron microscopy (FESEM) in microstructure scale to observe the fracture mechanism. Observed different failure mode in fiber and resin. Chemical composition of composite and fibers were investigated by using electron dispersive x-ray (EDX) spectroscopy that gave out in 88 w.t % of carbon and 12 w.t % in carbon fiber twill (CFT) composite. On the other hand, glass fiber woven (GFW) composite contained 72.7 w.t % of C, 20.7 w.t % of O2, and the rest contained Si, Ca, Al, Mg and Cl.
Solid‐oxide Li + electrolytes of a rechargeable cell are generally sensitive to moisture in the air as H + exchanges for the mobile Li + of the electrolyte and forms insulating surface phases at the electrolyte inter...
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Solid‐oxide Li + electrolytes of a rechargeable cell are generally sensitive to moisture in the air as H + exchanges for the mobile Li + of the electrolyte and forms insulating surface phases at the electrolyte interfaces and in the grain boundaries of a polycrystalline membrane. These surface phases dominate the total interfacial resistance of a conventional rechargeable cell with a solid–electrolyte separator. We report a new perovskite Li + solid electrolyte, Li 0.38 Sr 0.44 Ta 0.7 Hf 0.3 O 2.95 F 0.05 , with a lithium‐ion conductivity of σ Li =4.8×10 −4 S cm −1 at 25 °C that does not react with water having 3≤pH≤14. The solid electrolyte with a thin Li + ‐conducting polymer on its surface to prevent reduction of Ta 5+ is wet by metallic lithium and provides low‐impedance dendrite‐free plating/stripping of a lithium anode. It is also stable upon contact with a composite polymer cathode. With this solid electrolyte, we demonstrate excellent cycling performance of an all‐solid‐state Li/LiFePO 4 cell, a Li‐S cell with a polymer‐gel cathode, and a supercapacitor.
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