Recent developments in 2D nanomaterials have greatly expanded their use in engineering applications. Graphitic carbon nitride (g-C3N4) shows a combination of electrical conductivity, sensing and luminescence abilities...
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An interesting connection between shark spiral intestines and the Tesla valve was proposed recently;however, how Tesla valves interact with active matters and the potential applications of Tesla valves in biology rema...
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Strongly enhanced electron-electron interaction in semiconducting moiré superlattices formed by transition metal dichalcogenides (TMDCs) heterobilayers has led to a plethora of intriguing fermionic correlated sta...
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Faradaic deionization (FDI) is a promising technology for energy-efficient water desalination using porous electrodes containing redox-active materials. Herein, we demonstrate for the first time the capability of a sy...
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Scanning photocurrent microscopy (SPCM) has been widely used for characterizing charge transport properties, in particular, the minority carrier diffusion length of semiconductors. However, studying lightly doped or i...
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The usage of electric vehicles will contribute to a decrease in greenhouse gas emissions and rising fuel costs. To promote acceptance of electrified mobility, a variety of charging networks must be established in an a...
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Hydrogen storage in metal hydrides has been extensively studied due to their capacity to reversibly absorb hydrogen under relatively low pressures. Multicomponent alloys, especially those of the Ti-V-Nb-Cr system, hav...
Hydrogen storage in metal hydrides has been extensively studied due to their capacity to reversibly absorb hydrogen under relatively low pressures. Multicomponent alloys, especially those of the Ti-V-Nb-Cr system, have garnered significant attention because of the possibility of fine-tuning the hydrogen storage properties by compositional control. However, most of the investigations on multicomponent alloys rely on high-purity elements as feedstock materials, which can have a substantial environmental impact due to the energy-intensive processes required to achieve such purity levels. In this work, we propose an alternative approach by utilizing Ti6Al4V alloy (ASTM F136) scraps from the biomedical industry as feedstock material to produce Ti18Nb23V24Cr33Al2. The alloy was synthesized by using an arc-melting process, combining Ti6Al4V scraps with other pure elements. Structural analysis using X-ray diffraction (XRD) and scanning electron microscopy (SEM) revealed the formation of a microstructure composed predominantly by a body-centered cubic (BCC) solid solution with a small micro segregation providing additional microstructural insights. The Ti18Nb23V24Cr33Al2alloy exhibited a hydrogen storage capacity of 2.75 wt % H2with room temperature reversibility, presenting hydrogen storage properties comparable to those of a (TiVNb)65Cr35alloy produced only from high-purity *** study presents a sustainable approach to producing Ti18Nb23V24Cr33Al2alloy from Ti6Al4V machine chips, achieving efficient hydrogen storage with reduced environmental impact.
In this paper, we introduce a first-principles-based lattice mode analysis method to investigate the competition between different polarization switching paths in HfO2. Because the stability of the polar orthorhombic ...
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In this paper, we introduce a first-principles-based lattice mode analysis method to investigate the competition between different polarization switching paths in HfO2. Because the stability of the polar orthorhombic Pca21 phase of HfO2 arises from a trilinear coupling, polarization switching requires the flipping of not only the polar Γ15Z mode, but also at least one zone-boundary antipolar mode. This means that each polarization state has multiple variants, leading to multiple possible switching paths connecting up- and down-polarized states, which can be systemically enumerated within this framework for efficient identification of the optimal switching path. Our lattice mode analysis also explains why the activation energy of propagation of the most widely studied domain-wall structure in HfO2, which requires the reversal of the X2− mode, is much larger than that of propagation of domain-wall structures with a uniform sign for the X2− mode. This approach deepens our understanding of distinctive properties of ferroelectric HfO2 related to polarization switching and domain-wall motion, including sluggish domain-wall motion, robust ferroelectricity in thin films, and the observation that the antipolar Pbca phase can hardly be transformed to the ferroelectric Pca21 phase by an electric field. Our mode analysis method can be more generally applied to any improper or hybrid improper ferroelectric, in which polarization switching requires changes of nonpolar distortions, for systematic and efficient prediction of optimal switching paths and estimation of coercive fields.
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