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The electrochemical reduction (ECR) of CO2 is a promising approach for CO2 removal and utilization, which is a critical component of the circular carbon economy. However, developing efficient and selective electrocatalysts is still challenging. Single-atom catalysts (SACs) have gained attention because they offer high metal atom utilization and uniform active sites. However, tuning the active metal centres to achieve high activity and selectivity in CO2 reduction remains a significant challenge. This study presents a novel electrocatalyst (Co–Ni–N–C) for CO2 ECR on the diatomic metal–nitrogen sites prepared through ion exchange using a zeolitic imidazolate framework (ZIF) as a precursor. During pyrolysis, nitrogen-doped graphitic carbon serves as the host material, anchoring the diatomic Co–Ni sites. The resulting bimetallic active sites demonstrate exceptional performance, achieving a high CO yield rate of 53.36 mA mgcat.−1 and an impressive CO faradaic efficiency of 94.1% at an overpotential of −0.27 V. Spectroscopic, microscopic, and density functional theory (DFT) analyses collectively unveil the crucial synergistic role of the Co–Ni–N6 moiety in promoting and sustaining exceptional electrocatalytic activities. The successful utilization of bimetallic sites in enhancing catalyst performance highlights the potential of this approach in developing efficient electrocatalysts for various other reactions. [ABSTRACT FROM AUTHOR]

In this study, a resistive random-access memory device based on a Ta/TaxMnyOz/Pt metal–insulator–metal structure was fabricated and examined. The test device exhibited stable bipolar resistive switching characteristics with DC endurance of more than 300 cycles and robust retention up to 104 s at room temperature. Moreover, the device had a low forming voltage and a resistance window of ~ 103. The conduction mechanism in each resistance state of the device was analyzed through current–voltage curve fitting. It was confirmed that the primary conduction mechanisms were ohmic and Poole–Frenkel conduction in the low- and high-resistance states, respectively. By analyzing the cross section of the fabricated device through transmission electron microscopy, it was found that the TaxMnyOz layer was deposited in amorphous form. The composition and chemical bonding state of the TaxMnyOz layer were also analyzed using X-ray photoelectron spectroscopy. With these characteristics, the amorphous TaxMnyOz layer has strong potential for nonvolatile memory applications. [ABSTRACT FROM AUTHOR]

Niobium superconducting radiofrequency cavities enable applications in modern accelerators and quantum computers. However, the surface resistance significantly deteriorates the cavities' performance. Nitrogen doping surface treatment can consistently increase cavity performance by reducing surface resistance, but the improvement mechanism is not fully understood. Herein, we employed transmission electron microscopy and spectroscopy to uncover the structural and chemical differences of the Nb/air interface between the non-doped and nitrogen-doped cavities. The results indicate that nitrogen doping passivates the Nb surface by introducing a compressive stress/strain close to the Nb/air interface, which impedes the diffusion of oxygen and hydrogen atoms and reduces surface oxide thickness. A comprehensive structural and chemical study of the Nb/air interface from the non-doped and nitrogen-doped niobium cavity helps to understand the performance improvement mechanisms of the nitrogen-doped cavity. [ABSTRACT FROM AUTHOR]

The quantity of the crystalline phases present in a nanomaterial is an important parameter that governs the correlation between its properties and microstructure. However, quantification of crystallinity in nanoscale‐level applications by conventional methods (Raman spectroscopy and X‐ray diffraction) is difficult because of the spatial limitations of sampling. Therefore, we propose a technique that involves using energy‐filtered electron diffraction in transmission electron microscopy which offers improved spatial resolution. The degree of crystallinity (DOC) was calculated by separating the crystalline and amorphous intensities from the total intensity histogram acquired by the azimuthal averaging of the zero‐loss filtered signals from electron diffraction. In order to validate the method, it was demonstrated that the DOC calculated by zero‐loss filtered electron diffraction was consistent with the DOC measured by the area ratio using an amorphous silicon on crystalline silicon standard sample. In addition, the results obtained from zero‐loss filtered and conventional electron diffractions were compared. The zero‐loss filtered electron diffraction successfully provided the reliable results of the crystallinity quantification. In contrast, the DOC measured using conventional electron diffraction yielded extremely variable results. Therefore, our results provide a crystallinity quantification technique that can extract quantitative information about crystallinity of nanoscale devices by using zero‐loss filtered electron diffraction with better reliability than conventional electron diffraction. Research highlights: The degree of crystallinity can be measured by separating the crystalline and amorphous intensities from the total intensity histogram acquired by the azimuthal averaging of the zero‐loss filtered signals from selected area electron diffraction. The degree of crystallinity can be measured by separating the crystalline and amorphous intensities from the total intensity histogram acquired by the azimuthal averaging of the zero‐loss filtered signals from selected area electron diffraction. [ABSTRACT FROM AUTHOR]

The prevalence of atopic dermatitis (AD), a disease characterized by severe pruritus, immune imbalance, and skin barrier dysfunction, is rapidly increasing worldwide. Deacetylasperulosidic acid (DAA) has anti-atopic activity in the three main cell types associated with AD: keratinocytes, mast cells, and eosinophils. Our study investigated the anti-atopic activity of DAA in 2,4-dinitrochlorobenzene-induced NC/Nga mice. DAA alleviated the symptoms of AD, including infiltration of inflammatory cells (mast cells and eosinophils), epidermal thickness, ear thickness, and scratching behavior. Furthermore, DAA reduced serum IgE, histamine, and IgG1/IgG2a ratio and modulated the levels of AD-related cytokines and chemokines, namely interleukin (IL)-1β, IL-4, IL-6, IL-9, IL-10, IL-12, tumor necrosis factor-α, interferon-γ, thymic stromal lymphopoietin, thymus and activation-regulated chemokine, macrophage-derived chemokine, and regulated on activation the normal T cell expressed and secreted in the serum. DAA restored immune balance by regulating gene expression and secretion of Th1-, Th2-, Th9-, Th17-, and Th22-mediated inflammatory factors in the dorsal skin and splenocytes and restored skin barrier function by increasing the expression of the pro-filaggrin gene and barrier-related proteins filaggrin, involucrin, and loricrin. These results suggest DAA as a potential therapeutic agent that can alleviate the symptoms of AD by reducing pruritus, modulating immune imbalance, and restoring skin barrier function. [ABSTRACT FROM AUTHOR]

Improving the qubit's lifetime (T 1 ) is crucial for fault-tolerant quantum computing. Recent advancements have shown that replacing niobium (Nb) with tantalum (Ta) as the base metal significantly increases T 1 , likely due to a less lossy native surface oxide. However, understanding the formation mechanism and nature of both surface oxides is still limited. Using aberration-corrected transmission electron microscopy and electron energy loss spectroscopy, we found that Ta surface oxide has fewer suboxides than Nb oxide. We observed an abrupt oxidation state transition from Ta 2 O 5 to Ta, as opposed to the gradual shift from Nb 2 O 5 , NbO 2 , and NbO to Nb, consistent with thermodynamic modeling. Additionally, amorphous Ta 2 O 5 exhibits a closer-to-crystalline bonding nature than Nb 2 O 5 , potentially hindering H atomic diffusion toward the oxide/metal interface. Finally, we propose a loss mechanism arising from the transition between two states within the distorted octahedron in an amorphous structure, potentially causing two-level system loss. Our findings offer a deeper understanding of the differences between native amorphous Ta and Nb oxides, providing valuable insights for advancing superconducting qubits through surface oxide engineering.