Publications by authors named "Yiwa Luo"
Despite its existence for more than 80 years, the titanium industry is still challenged by massive carbon emissions, high production costs, and large resource waste. More than one hundred million tons of Ti-bearing blast furnace slag (TB-slag) has been discarded in China because of the difficulty of reutilization, which requires efficient titanium extraction and recovery technologies. This paper describes a low-cost, carbon-emission-free method for Ti extraction and oxygen evolution via molten oxide electrolysis (MOE) vacuum distillation.
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- Volume expansion of electrodes during ion intercalation in aluminum-ion batteries (AIBs) can weaken adhesion to current collectors, leading to potential detachment issues.
- A new concept called the "dead zone" is introduced, which uses a surface modification of MXene film to create a negative-charge region that repels AlCl intercalation, forming a protective inert layer.
- This innovation significantly improves electrode adhesion and extends battery cycle life to up to 50,000 cycles, suggesting a promising direction for future advancements in current collectors for different battery types.
As one of the emerging safe energy-storage devices with high energy-to-cost ratio, nonaqueous aluminum batteries with enhanced energy density are intensively pursued by researchers. Although significant progress has been made on positive electrode materials, the effective energy density of aluminum batteries is still limited by the presence of high-density refractory metal current collectors, which are known to be electrochemically inert in highly acidic ionic-liquid electrolytes. To address such critical issues, here, a novel low-density (<2 g cm ) nonmetal current collector is presented, which uses poly(ethylene terephthalate) (PET) substrates coated with indium tin oxide (ITO), with the purpose of significantly reducing the ratio of nonactive components in the electrodes.
View Article and Find Full Text PDFRechargeable aluminum-ion batteries (AIBs) possess significant advantages of high energy density, safety performance, and abundant natural resources, making them one of the desirable next-generation substitutes for lithium battery systems. However, the poor reversibility, short lifespan, and low capacity of positive materials have limited its practical applications. In comparison with semiconductors, the metallic nickel telluride (NiTe) alloy with enhanced electrical conductivity and fast electron transmission is a more favorable electrode material that could significantly decrease the kinetic barrier during battery operation for energy storage.
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- - The Fe-Co-Cr-Mo-W-V-C alloy, known for its excellent hardness, is widely used in manufacturing cutting tools, but it faces cracking issues due to poor hot ductility during processing.
- - This study investigates the microstructural characteristics and carbide transformations of the alloy in both as-cast and wrought states, revealing key carbides like Mo₂C and VC, with Cr₇C₃ showing the best mechanical properties to resist cracking.
- - Hot isothermal compression tests were conducted to simulate the alloy's behavior during deformation, leading to the establishment of a constitutive equation that correlates true stress, strain rate, and temperature, ultimately optimizing the forging process for better microstructure.
Article Synopsis
- * It finds that at the lower tempering temperature (773⁻803 K), there are more carbide particles, particularly those smaller than 5 μm, compared to the higher temperature range (823⁻853 K), leading to a notable reduction in wear loss.
- * The research concludes that Al₂O₃ inclusions enhance carbide formation by acting as nucleation sites, with lower cooling temperatures favoring more significant carbide precipitation due to differences in solubility during steel
Article Synopsis
- The study investigated how nitrogen affects carbide structures in AISI M42 high-speed steel during casting and heat treatment processes.
- It was found that nitrogen addition influences the formation of fibrous and lamellar MC carbides, with fibrous being more stable when subjected to forging and annealing.
- Ultimately, the presence of nitrogen improved the distribution and dimensions of carbides, leading to enhanced impact toughness in the steel.