Publications by authors named "Tim Eldred"

Article Synopsis
  • Direct observation of solid-state chemical reactions can uncover hidden mechanisms influencing reaction rates, but current methods struggle with spatial and temporal resolution.
  • Using advanced atomic-resolution imaging techniques in electron microscopy, researchers visualized the decomposition of KPtCl, identifying transient phases and interfaces during the chemical reduction process.
  • The study revealed a sequence of reactions from KPtCl to crystalline Pt metal and KCl, establishing a link between initial and final states of the reaction, which highlights potential for new insights into reaction pathways at the atomic level.
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Transmission electron microscopy (TEM) enables users to study materials at their fundamental, atomic scale. Complex experiments routinely generate thousands of images with numerous parameters that require time-consuming and complicated analysis. AXON synchronicity is a machine-vision synchronization (MVS) software solution designed to address the pain points inherent to TEM studies.

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Magnetic transition metal chalcogenides form an emerging platform for exploring spin-orbit driven Berry phase phenomena owing to the nontrivial interplay between topology and magnetism. Here we show that the anomalous Hall effect in pristine CrTe thin films manifests a unique temperature-dependent sign reversal at nonzero magnetization, resulting from the momentum-space Berry curvature as established by first-principles simulations. The sign change is strain tunable, enabled by the sharp and well-defined substrate/film interface in the quasi-two-dimensional CrTe epitaxial films, revealed by scanning transmission electron microscopy and depth-sensitive polarized neutron reflectometry.

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High-entropy oxides (HEOs) have a large tuning space in composition and crystal structures, offering the possibility for improved material properties in applications including catalysis, energy storage, and thermal barrier coatings. Understanding the nucleation and growth mechanisms of HEOs at the atomic scale is critical to the design of their structure and functions but remains challenging. Herein, we visualize the entire formation process of a high-entropy fluorite oxide from a polymeric precursor using atomic resolution gas-phase scanning transmission electron microscopy.

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Oxidative dehydrogenation (ODH) of -butane has the potential to efficiently produce butadiene without equilibrium limitation or coke formation. Despite extensive research efforts, single-pass butadiene yields are limited to <23% in conventional catalytic ODH with gaseous O. This article reports molten LiBr as an effective promoter to modify a redox-active perovskite oxide, i.

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Article Synopsis
  • Development in lattice strain mapping using 4D-STEM has improved precision, but automatic diffraction analysis remains difficult due to noise and complex patterns.
  • This work presents a new method that uses blob detection and lattice fitting to automate data processing without prior knowledge of the material.
  • The method is effective for both simulated and experimental data, demonstrating high accuracy and robustness against varying sample conditions.
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Protocols to create metal-organic framework (MOF)/polymer composites for separation, chemical capture, and catalytic applications currently rely on relatively slow solution-based processing to form single MOF composites. Here, we report a rapid, high-yield sorption-vapor method for direct simultaneous growth of single and multiple MOF materials onto untreated flexible and stretchable polymer fibers and films. The synthesis utilizes favorable reactant absorption into polymers coupled with rapid vapor-driven MOF crystallization to form high surface area (>250 m/g) composites, including UiO-66-NH, HKUST-1, and MOF-525 on spandex, nylon, and other fabrics.

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As human health concerns over disinfection byproducts (DBP) in drinking water increase, so does the need to develop new materials that remove them rapidly and at high capacity. Ion exchange (IEX) is an effective method for the removal of natural organic matter (NOM), especially anion exchange resins (AERs) with quaternary ammonium functional groups. However, capacity is limited in existing commercial resin materials because adsorbates can only interact with the outermost surface area, which makes these products inefficient on a mass basis.

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