MRS Communications最新文献

In this work, the functionalization of SnO₂ nanowires with grafted hydroxyl (OH) groups was introduced by changing the post-synthetic treatment and by growth in a vapor phase. Besides, the present paper describes two types of growth methods: (i) the vapor–solid one with post-synthesis treatment under NaOH solutions with different pH, and (ii) the direct growth using the vapor–liquid–solid one under water vapor. Structural characterizations demonstrated that OH groups were successfully anchored. Notably, band gap changes in the presence of OH groups are revealed. This kind of surface state engineering precisely opens new avenues of SnO₂ nanowire applications in sensors and semiconductor uses.

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This article reviews the recent progress in fabricating microfluidic devices and soft robots using direct ink writing (DIW) three-dimensional (3D) printing with silicone elastomers. Additive manufacturing, especially 3D printing, has become an alternative method to traditional soft lithography for producing microchannels, establishing a new standard in the field of microfluidics. This approach offers unprecedented opportunities for digital control, automation, and the elimination of manual assembly. Among different 3D printing technologies, DIW 3D printing facilitates the accurate deposition of liquid silicone precursors on various substrates in the air or liquid media, enabling the fabrication of microfluidic structures using a one-part room-temperature-vulcanizing (RTV) silicone sealant and two-part addition-curing silicone elastomers. The effectiveness of DIW 3D printing is demonstrated through (1) creating microchannels on various substrates, (2) printing interconnected, multilayer microchannels without the need for sacrificial support materials or extensive post-processing steps, and (3) integrating electronic components into microchannels during the printing process. In this article, overviews of the fabrication of microfluidic devices using 3D printing are provided first, followed by a discussion of different criteria and approaches for DIW 3D printing of silicone-based elastomeric structures in open-air and embedded media. Next, the structure–property relations of silicone-based microfluidic devices are discussed. Then, examples of DIW-fabricated silicone microfluidic devices and soft robotics are showcased, highlighting the unique benefits and opportunities of the methods. Finally, current challenges and future directions in DIW 3D printing of microfluidic systems are discussed.

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In the presence of ethylenediaminetetraacetic acid (EDTA), a straightforward hydrothermal method was conceptualized for the purpose of controlling the size and form of the zircon-type tetragonal phase of LaVO₄:Eu nanostructures. Nanorods and nanosheaves have been selectively obtained by tuning the pH value. In particular, LaVO₄:Eu nanorods covered by EDTA molecules are soluble in water. In addition, research on photoluminescence has demonstrated that Eu³⁺-doped LaVO₄ nanorods exhibit significant red emission when exposed to ultraviolet light. This phenomenon has the potential to be utilized in a variety of disciplines, including visual display, catalysis, and biological imaging.

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Abstract

We develop a materials informatics workflow to build an interpretable surrogate model for micromagnetic simulations. Our goal is to predict the energy barrier of a moving isolated skyrmion in rare-earth-free (hbox {Mn}_4)N. Our approach integrates adaptive learning with post hoc model explanation and symbolic regression methods. We discuss an unexplored acquisition function (information condensing active learning) within the adaptive learning loop and compare it with the known standard deviation function for efficient navigation of the search space. Model-agnostic post hoc explanation techniques then uncover trends learned by the trained model, which we then leverage to constrain the expressions used for symbolic regression.

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The cobalt-promoted MoS₂ microspheres have been synthesized by hydrothermal methods using sodium molybdate precursors. Scanning electron microscopy indicates that spherical shape morphology and cobalt atoms are detected at MoS₂ edges corresponding to (101)-plane as revealed by Cs-corrected transmission electron microscopy. The magnetic states were measured by magnetization curves obtaining a 0.044 emu/g due to paramagnetic contribution. Furthermore, the electronic structure from the density of states for 2H-MoS₂ with and without cobalt at the (101) edge plane possesses a magnetic property with a value of 0.16 μ_B attributed to broken symmetry.

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Memristors are utilized in nonvolatile memory and artificial synaptic devices. However, the industrial application of memristors has been restricted by the occurrence of fatigue, the mechanism of which is still under debate. In this paper, we systematically investigated the mechanism of defect generation created by Joule heating in Cu-doped TiO₂ memristive device. The results also demonstrated that the Joule heat for artificial synaptic emulation was less severe than that for digital data storage.

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Organic materials have found widespread applications but require doping to overcome their intrinsically low carrier concentration. Doping injects free carriers into the polymer, moving the position of the Fermi level, and creates coulombic traps, changing the shape of the electronic density of states (DOS). We develop equations to explicitly map the DOS parameters to the Seebeck vs conductivity relationship. At low carrier concentrations, this relationship is a universal slope (-{k}_{B}/q), while at higher carrier concentrations, the slope becomes dependent on the shape of the DOS. We conclude that, at high doping, a heavy-tailed DOS leads to higher thermoelectric power factors.

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LaAlO₃ nanofibers are prepared using reproducible and green electrospinning technique. Particularly, N,N-dimethylformamide (DMF) and acetic acid/water (A-A/W) were used as solvents. The structural and textural properties were compared. Results indicate that the diameter of as-spun nanofibers with (A-A/W) ranged from 50 to 400 nm. While it is between 100 and 600 nm for (DMF). After calcination, it decreased to an average of 80 nm for (A-A/W) and 200 nm for (DMF). Higher pore volume (0.69 cc g⁻¹) and surface area (176.3 m² g⁻¹) were achieved for (A-A/W) solvent. The textural properties confirm that LaAlO₃ exhibit high performances for advanced technologies mainly sensors.

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We described optical properties of zinc oxide (ZnO) nanoparticles determined by spectroscopic ellipsometry analysis from ex situ spectroscopic ellipsometry (ex situ SE) measurements made on nanocrystalline thin films over a spectral range of 0.734 to 4.00 eV. We determined the complex refractive index function, (widetilde{n}(omega )=n(omega )+ikappa (omega )), by fitting a layered parametric model to the ellipsometric measurements. We collected SE measurements at an incidence angle of 70°. We also determined absorption coefficient spectra using extinction coefficient, κ and wavelength, λ. The direct optical bandgap of the films was obtained as 3.2 eV using the ellipsometric method.

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This paper introduces and explains cyber physics, which we define as mathematical equations, i.e., physics-like laws, that control, regulate, or otherwise govern the inner workings of the hardware architecture, operating system, application code, algorithms, and networks on a classical computing machine. Cyber physics integrates computer science with conventional physics, in particular with quantum physics, thermodynamics, and statistical mechanics. Naturally, the technical description of cyber physics in the paper draws on both of these fields of science.

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