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Exploring the unique physical properties of oxide perovskites necessitates their growth on diverse single‐crystal substrates. The thin‐film growth of perovskite SrMnO3 (SMO) has been a particular focus of research due to its emerging room‐temperature multiferroicity. Herein, the epitaxial thin films of (110)‐oriented SMO are grown on the piezoelectric (110)‐oriented (1–x)Pb(Mg1/3Nb2/3)O3–xPbTiO3 (PMN‐PT) substrate. The effects of the thickness and oxygen annealing on the crystal structure, stoichiometry, and ferroelectric properties of the SMO thin film are systematically investigated. The tensile strain produced by the lattice mismatch between the bulk SMO and the PMN‐PT substrate causes an expansion of the c‐lattice parallel to the in‐plane direction of the substrate. The films show larger a‐, b‐, and c‐lattice parameters than the bulk material, resulting in volume expansion of the unit cell. This lattice expansion is attributed to the generation of oxygen vacancies driven by the reduced formation energy caused by the high elastic strain. Piezoelectric force microscopy reveals that the SMO film contains domains with strain‐mediated in‐plane and vacancy‐mediated out‐of‐plane polarization. Furthermore, the piezoelectric response of the PMN‐PT substrate effectively modulates the biaxial tensile strain in the SMO film, offering a potential strategy for controlling the crystal structure and ferroelectric properties of SMO. [ABSTRACT FROM AUTHOR]

High-throughput materials research is strongly required to accelerate the development of safe and high energy-density lithium-ion battery (LIB) applicable to electric vehicle and energy storage system. The artificial intelligence, including machine learning with neural networks such as Boltzmann neural networks and convolutional neural networks (CNN), is a powerful tool to explore next-generation electrode materials and functional additives. In this paper, we develop a prediction model that classifies the major composition (e.g., 333, 523, 622, and 811) and different states (e.g., pristine, pre-cycled, and 100 times cycled) of various Li(Ni, Co, Mn)O2 (NCM) cathodes via CNN trained on scanning electron microscopy (SEM) images. Based on those results, our trained CNN model shows a high accuracy of 99.6% where the number of test set is 3840. In addition, the model can be applied to the case of untrained SEM data of NCM cathodes with functional electrolyte additives. [ABSTRACT FROM AUTHOR]

Electrolyte additives with multiple functions enable the interfacial engineering of Li‐metal batteries (LMBs). Owing to their unique reduction behavior, additives exhibit a high potential for electrode surface modification that increases the reversibility of Li‐metal anodes by enabling the development of a hierarchical solid electrolyte interphase (SEI). This study confirms that an adequately designed SEI facilitates the homogeneous supply of Li+, nonlocalized Li deposition, and low electrolyte degradation in LMBs while enduring the volume fluctuation of Li‐metal anodes on cycling. An in‐depth analysis of interfacial engineering mechanisms reveals that multilayered SEI structures comprising mechanically robust LiF‐rich species, electron‐rich P–O species, and elastic polymeric species enabled the stable charge and discharge of LMBs. The polymeric outer SEI layer in the as‐fabricated multilayered SEI could accommodate the volume fluctuation of Li‐metal anodes, significantly enhancing the cycling stability Li||LiNi0.8Co0.1Mn0.1O2 full cells with an electrolyte amount of 3.6 g Ah−1 and an areal capacity of 3.2 mAh cm−2. Therefore, this study confirms the ability of interfacial layers formed by electrolyte additives and fluorinated solvents to advance the performance of LMBs and can open new frontiers in the fabrication of high‐performance LMBs through electrolyte‐formulation engineering. [ABSTRACT FROM AUTHOR]

This study investigates the impact of resonant acoustic powder mixing on the delay time of the W–KClO4–BaCrO4 (WKB) mixture and its potential implications for powder and material synthesis. Through thermal analysis, an inverse linear relationship was found between thermal conductivity and delay time, allowing us to use thermal conductivity as a reliable proxy for delay time. By comparing the thermal conductivity of WKB mixtures mixed manually and using an acoustic powder mixer, we found that acoustic powder mixing resulted in minimal deviations in thermal conductivity, proving more uniform mixing. Furthermore, differential scanning calorimeter analysis and Sestak–Berggren modeling demonstrated consistent reaction dynamics with a constant activation energy as the reaction progressed in samples mixed using acoustic waves. These findings underscore the critical role of uniform powder mixing in enhancing the thermodynamic quality of the WKB mixture and emphasize the importance of developing novel methods for powder and material synthesis. [ABSTRACT FROM AUTHOR]

In this study, a mechanically flexible structure, a cuboctahedral metal‐organic polyhedra (MOP) Cu24[5‐(octyloxy) isophthalic acid]24 Cu (II) paddlewheel clusters coordinated with (5‐(octyloxy) isophthalate), resulting in significantly enhanced hydrolytic stability are prepared. It should be noted that CuMOP‐1 exhibits evenly and symmetrically distributed non‐polar long alkyl chains and polar hydroxy groups, facilitating self‐assembly into higher‐order structures reminiscent of amphiphiles. Furthermore, the resultant CuMOP‐1 undergoes a phase change at 150–160 °C as confirmed temperature‐dependent Raman spectroscopy (RS), thermogravimetric analysis and Differential Scanning Calorimetry (TGA‐DSC). The possible use of Cu‐MOP‐1 for capturing mechanical energy is demonstrated by creating a flexible hybrid piezoelectric‐triboelectric nanogenerator (HP‐TENG). The resultant CuMOP‐1@ Polyvinylidene fluoride(PVDF) membrane‐based HP‐TENG demonstrates enhanced triboelectric output voltage of 547.5 V, current density of 15.16 µAcm−2, and power density of 2.8 mWcm−2 due to its increased surface charge density and a substantial rise in the dielectric constant. Furthermore, the amphiphiles and phase change in CuMOP‐1 lead to ∽73% increase in voltage and 60% in current density of HP‐TENG in high‐temperature (140 °C) environments. HP‐TENG also exhibits exceptional temperature‐ and pressure‐sensing abilities, with sensitivities of 1.81 V°C−1 and 7.12 V°kPa−1, respectively, showcasing its feasibility over a wide range of temperatures and pressures. [ABSTRACT FROM AUTHOR]

Recently, in electric mobilities and stationary energy storage device applications, the development of long‐lasting, low‐cost, and high‐safety lithium‐ion batteries (LIBs) is widely studied. LiFePO4 (LFP) is a core cathode material for LIBs owing to its cost‐effectiveness and high safety. However, it exhibits low electronic conductivity and sluggish Li+ diffusion, hindering the application of LFP cathodes in high‐power battery industries. Herein, a triazole‐motivated electrolyte additive, 1‐(trimethylsilyl)−1H‐benzotriazole (TMSBTA) is presented, for mitigating iron dissolution via HF scavenging, reinforcing the robustness of the solid electrolyte interphase and constructing a cathode–electrolyte interface (CEI) to balance the ion and electron conduction of the CEI on the LFP cathode. Scanning probe microscopy performed in the conductive atomic force microscopy mode indicates that the electronically conductive CEI created by the oxidative decomposition of TMSBTA enables rapid and homogeneous lithiation and delithiation during cycling without morphological changes in the LFP particles. This study elucidates the design principles of the CEI on the LFP cathode and is expected to guide integrated electrolyte additive engineering for LFP‐containing LIBs. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the most frequent neurodegenerative disorder in the elderly aged over 65. The extracellular accumulation of beta-amyloid (Aβ) aggregates in the brain is considered as the major event worsening the AD symptoms, but its underlying reason has remained unclear. Here the piezoelectric characteristics of Aβ aggregates are revealed. The vector piezoresponse force microscopy (PFM) analysis results exhibit that Aβ fibrils have spiraling piezoelectric domains along the length and a lateral piezoelectric constant of 44.1 pC N -1 . Also, the continuous sideband Kelvin probe force microscopy (KPFM) images display that the increment of charge-induced surface potential on a single Aβ fibril is allowed to reach above +1700 mV in response to applied forces. These findings shed light on the peculiar mechano-electrical surface properties of pathological Aβ fibrils that exceed those of normal body components., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Halide perovskite, renowned for its multifunctional properties, shows considerable promise for realizing self-charging power systems. In this study, a lead-free methylammonium bismuth iodide (MA 3 Bi 2 I 9 ) perovskite is used to create a self-charging power unit (SPU). This involves constructing a hybrid piezoelectric-triboelectric nanogenerator (Hybrid-TENG) and utilizing MA 3 Bi 2 I 9 for energy storage as an anode in a lithium-ion battery (LIB). Initially, MA 3 Bi 2 I 9 nanorods are synthesized and composited with a polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene polymer. The dielectric and mechanical properties of composite films having perovskite loading content are investigated. The optimized Hybrid-TENG exhibits superior performance, generating a voltage of 537 V, current density of 13.2 µA cm - 2 , and maximum power density of 3.04 mW cm -2 , which can be attributed to the high piezoelectric coefficient of MA 3 Bi 2 I 9 nanorods (≈20.6 pm V -1 ). A MA 3 Bi 2 I 9 thin film, serving as an electrode in LIB, demonstrates a high specific capacity of 2378.9 mAh cm -3 (578.8   mAh g -1 ) with a capacity retention of ≈87.5% over 100 cycles, underscoring its stable performance. Furthermore, a Hybrid-TENG is employed to charge the MA 3 Bi 2 I 9 -based LIB, thus realizing an SPU for driving portable electronics. This study highlights the promising potential of perovskites for developing efficient nanogenerators and LIBs, paving the way for sustainable energy solutions in small-scale electronics., (© 2024 Wiley‐VCH GmbH.)