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The crystalline structures and magnetic and thermodynamic properties of a Gd4Ga2O9 single crystal grown with the optical floating zone technique have been investigated. Gd4Ga2O9 crystallizes in a monoclinic structure with the space group P21/c at room temperature. Temperature‐dependent magnetic susceptibility measurements along the three crystallographic axes reveal a paramagnetic (PM) behavior between 2 and 300 K. A Curie–Weiss (CW) law fit was carried out and the CW temperature gθCW and magnetic frustration parameter f were calculated; these suggest antiferromagnetic (AFM) interactions between Gd3+ spins and a strong magnetic frustration. The field dependence of the magnetization at 2 K further confirms the magnetic frustration characteristics. A distinct λ‐shaped peak at 1.4 K in the heat capacity curves suggests a transition from the PM to AFM phase. The magnetic entropy is contributed solely by Gd3+ ions. [ABSTRACT FROM AUTHOR]

The crystalline structures and magnetic and thermodynamic properties of a Gd4Ga2O9 single crystal grown with the optical floating zone technique have been investigated. Gd4Ga2O9 crystallizes in a monoclinic structure with the space group P21/c at room temperature. Temperature‐dependent magnetic susceptibility measurements along the three crystallographic axes reveal a paramagnetic (PM) behavior between 2 and 300 K. A Curie–Weiss (CW) law fit was carried out and the CW temperature gθCW and magnetic frustration parameter f were calculated; these suggest antiferromagnetic (AFM) interactions between Gd3+ spins and a strong magnetic frustration. The field dependence of the magnetization at 2 K further confirms the magnetic frustration characteristics. A distinct λ‐shaped peak at 1.4 K in the heat capacity curves suggests a transition from the PM to AFM phase. The magnetic entropy is contributed solely by Gd3+ ions. [ABSTRACT FROM AUTHOR]

Miniaturizing van der Waals (vdW) ferroelectric materials to atomic scales is essential for modern devices like nonvolatile memory and sensors. To unlock their full potential, their growth mechanisms, interface effects, and stabilization are preferably investigated, particularly for ultrathin 2D nanosheets with single‐unit cell thickness. This study focuses on Bi2TeO5 (BTO) and utilizes precise control over growth kinetics at the nucleation temperature to create specific interfacial reconfiguration layers. Ultrathin BTO nanosheets with planar ferroelectricity at a single‐unit cell thickness are successfully grown. Atomic‐scale characterization reveals a disordered distribution of elements in the interfacial layer, which buffers strain from lattice mismatch. The theoretical calculations support these observations. Furthermore, this strategy also can be extended to the growth of a variety of 2D ternary oxide nanosheets. This work contributes to a better understanding of growth and stability mechanisms in 2D ultrathin nanosheets. [ABSTRACT FROM AUTHOR]

High-entropy oxides (HEOs) are emerging as highly promising materials for electrochemical applications due to their exceptional electronic properties and active sites. However, the synthesis of 1D HEO with high aspect ratios and mechanical properties has been challenging, particularly on an industrial scale. Herein, we report a spatially confined oxidation (SCO) method to synthesize 1D HEO@SWCNTs with high specific surface area and stability. This method enables the large-scale production of HEO@SWCNTs, achieving quasi-industrially quantities in a single batch, and can be extended to seven-element 1D HEO. The resulting exhibit a homogeneous distribution of elements and a single-phase solid solution structure, as confirmed by STEM-EDS and XRD analysis. The Fermi level of SWCNTs is downshifted into the valence band upon HEO doping, enhancing conductivity and electrochemical activity. The HEO@SWCNTs electrode demonstrates superior flexibility and self-supported properties, making it suitable for large-scale electrochemical applications. Chronoamperometric measurements reveal excellent stability, maintaining 94% current retention after 20 h. Notably, in the electrochemical epoxidation reaction cycloolefin, the HEO@SWCNTs self-supported electrode achieves an average FE of 70.7% for epoxy-cyclohexane over 24 h. This work provides a scalable and versatile approach to the synthesis of self-supported electrodes for advanced electrochemical systems., (© 2025 Wiley‐VCH GmbH.)

Semiconducting single-wall carbon nanotubes (s-SWCNTs) represent one of the most promising materials for surpassing Moore's Law and developing the next generation of electronic devices. Despite numerous developed approaches, reducing the contact resistance of s-SWCNTs networks remains a significant challenge in achieving further enhancements in electronic performance. In this study, antimony triiodide (SbI 3 ) is efficiently encapsulated within high-purity s-SWCNTs films at low temperatures, forming 1D SbI 3 @s-SWCNTs vdW heterostructures. The semiconductor-metal transition of individual SbI 3 @s-SWCNTs is characterized via sensitive dielectric force microscopy, with the results confirmed through electrical device tests. The electrical behavior transition is attributed to an interlayer charge transfer, as demonstrated by Kelvin probe force microscopy. Moreover, the electrical performance of s-SWCNTs thin-film transistors improves significantly with SbI 3 @s-SWCNTs networks as contact electrodes. This process reduces the contact resistance between the s-SWCNTs channel and the electrodes, enhancing electrical performance. Specifically, the contact resistance decreases to one-third of the original, the carrier mobility increases by ≈10 times, the on-off ratio exceeds 10 6 , and the subthreshold swing reduces significantly to ≈65 mV dec -1 . These results demonstrate the effectiveness of inner-doping-induced metallization of s-SWCNTs in the contact region, essential for advancing carbon nanotube electronic devices and circuits., (© 2024 Wiley‐VCH GmbH.)

Rechargeable lithium-ion batteries are integral to contemporary energy storage, yet current anode material systems struggle to meet the increasing demand for extended range capabilities. This work introduces a novel composite anode material composed of one-dimensional 2H-phase tin disulfide (SnS 2 ) nanoribbons enclosed within cavities of single-walled carbon nanotubes (SnS 2 @SWCNTs), achieved through precise atomic engineering. Employing aberration-corrected transmission electron microscopy, we precisely elucidated the crystal structure of SnS 2 within the confines of the SWCNTs. This deliberate design effectively addresses the inherent limitations of SnS 2 as a lithium-ion anode material, including its low electrical conductivity, considerable volume expansion effects, and unstable solid electrolyte interface membrane. Testing confirmed that SnS 2 transforms into the Li 5 Sn 2 alloy phase after full lithiation and back to SnS 2 after delithiation, showing excellent reversibility. The composite also benefits from edge effects, improving lithium storage through stronger binding and lower migration barriers, which were supported by calculations. This pioneering work advances high-performance anode materials for applications.

Polymer-based solid-state batteries (SSBs) have received increasing attentions due to the absence of interfacial problems in sulfide/oxide-type SSBs, but the lower oxidation potential of polymer-based electrolytes greatly limits the application of conventional high-voltage cathode such as LiNi x Co y Mn z O 2 (NCM) and lithium-rich NCM. Herein, this study reports on a lithium-free V 2 O 5 cathode that enables the applications of polymer-based solid-state electrolyte (SSE) with high energy density due to the microstructured transport channels and suitable operational voltage. Using a synergistic combination of structural inspection and non-destructive X-ray computed tomography (X-CT), it interprets the chemo-mechanical behavior that determines the electrochemical performance of the V 2 O 5 cathode. Through detailed kinetic analyses such as differential capacity and galvanostatic intermittent titration technique (GITT), it is elucidated that the hierarchical V 2 O 5 constructed through microstructural engineering exhibits smaller electrochemical polarization and faster Li-ion diffusion rates in polymer-based SSBs than those in the liquid lithium batteries (LLBs). By the hierarchical ion transport channels created by the nanoparticles against each other, superior cycling stability (≈91.7% capacity retention after 100 cycles at 1 C) is achieved at 60 °C in polyoxyethylene (PEO)-based SSBs. The results highlight the crucial role of microstructure engineering in designing Li-free cathodes for polymer-based SSBs., (© 2023 Wiley-VCH GmbH.)