Strong enhancement of magnetic ordering temperature and structural/valence transitions in EuPd3S4 under high pressure.

We present a comprehensive study of the inhomogeneous mixed-valence compound, EuPd3S4, by electrical transport, X-ray diffraction, time-domain 151Eu synchrotron Mössbauer spectroscopy, and X-ray absorption spectroscopy measurements under high pressure. Electrical transport measurements show that the antiferromagnetic ordering temperature, TN, increases rapidly from 2.8 K at ambient pressure to 23.5 K at ~19 GPa and plateaus between ~19 and ~29 GPa after which no anomaly associated with TN is detected. A pressure-induced first-order structural transition from cubic to tetragonal is observed, with a rather broad coexistence region (~20 GPa to ~30 GPa) that corresponds to the TN plateau. Mössbauer spectroscopy measurements show a clear valence transition from approximately 50:50 Eu2+:Eu3+ to fully Eu3+ at ~28 GPa, consistent with the vanishing of the magnetic order at the same pressure. X-ray absorption data show a transition to a fully trivalent state at a similar pressure. Our results show that pressure first greatly enhances TN, most likely via enhanced hybridization between the Eu 4f states and the conduction band, and then, second, causes a structural phase transition that coincides with the conversion of the europium to a fully trivalent state.

Topological chiral crystals with helicoid-arc quantum states.

The quantum behaviour of electrons in materials is the foundation of modern electronics and information technology1-11, and quantum materials with topological electronic and optical properties are essential for realizing quantized electronic responses that can be used for next generation technology. Here we report the first observation of topological quantum properties of chiral crystals6,7 in the RhSi family. We find that this material class hosts a quantum phase of matter that exhibits nearly ideal topological surface properties originating from the crystals' structural chirality. Electrons on the surface of these crystals show a highly unusual helicoid fermionic structure that spirals around two high-symmetry momenta, indicating electronic topological chirality. The existence of bulk multiply degenerate band fermions is guaranteed by the crystal symmetries; however, to determine the topological invariant or charge in these chiral crystals, it is essential to identify and study the helicoid topology of the arc states. The helicoid arcs that we observe on the surface characterize the topological charges of ±2, which arise from bulk higher-spin chiral fermions. These topological conductors exhibit giant Fermi arcs of maximum length (π), which are orders of magnitude larger than those found in known chiral Weyl fermion semimetals5,8-11. Our results demonstrate an electronic topological state of matter on structurally chiral crystals featuring helicoid-arc quantum states. Such exotic multifold chiral fermion semimetal states could be used to detect a quantized photogalvanic optical response, the chiral magnetic effect and other optoelectronic phenomena predicted for this class of materials6.

Evidence of magnetism-induced topological protection in the axion insulator candidate EuSn2P2.

We unravel the interplay of topological properties and the layered (anti)ferromagnetic ordering in EuSn2P2, using spin and chemical selective electron and X-ray spectroscopies supported by first-principle calculations. We reveal the presence of in-plane long-range ferromagnetic order triggering topological invariants and resulting in the multiple protection of topological Dirac states. We provide clear evidence that layer-dependent spin-momentum locking coexists with ferromagnetism in this material, a cohabitation that promotes EuSn2P2 as a prime candidate axion insulator for topological antiferromagnetic spintronics applications.

Regulating Electrostatic Interaction between Hydrofluoroethers and Carbonyl Cathodes toward Highly Stable Lithium-Organic Batteries.

Organic carbonyl electrode materials have shown great promise for high-performance lithium batteries due to their high capacity, renewability, and environmental friendliness. However, their practical application is hindered by the high solubility of these materials in traditional electrolytes, leading to poor cycling stability and serious shuttle effects. Here, we develop a series of hydrofluoroethers (HFEs) with weak electrostatic interaction toward organic carbonyl cathode materials, aiming to address the dissolution issue and achieve high cycling stability in lithium batteries. Theoretical calculations reveal that the electrostatic interactions between HFEs and pyrene-4,5,9,10-tetraone (PTO) are significantly weaker compared with common solvents such as 1,2-dimethoxyethane. Consequently, the dissolution of PTO in the HFE-based electrolyte is remarkably reduced, as observed by in situ ultraviolet-visible spectra. Notably, when using the electrolyte based on 1,1,1,3,3,3-hexafluoro-2-methoxypropane with a certain coordination ability, PTO exhibits excellent cycling stability with a high capacity retention of 78% after 1000 cycles. This work proposes the regulation of electrostatic interactions to inhibit the dissolution of organic carbonyl cathode materials and significantly enhance their cycle life.

Nonaggregated Anions Enable the Undercooled Aqueous Electrolyte for Low-Temperature Applications.

Aqueous batteries, with the advantages of high safety and low cost, are highly promising for large-scale energy storage. However, freezing of the aqueous electrolyte limits the low-temperature operation. Here, we propose and achieve a highly dispersed solvation structure in the electrolyte by coupling nonaggregated Cl- anions, which reduces the water cluster size and prevents the solidification of the aqueous electrolyte until -136.3 °C. The low-temperature LiCl electrolyte exhibits a high ionic conductivity (1.0 mS cm-1) at -80 °C and enables a stable low-temperature Ag/AgCl reference electrode at -50 °C. Moreover, the polyaniline-based battery can work at an extremely low temperature of -100 °C and shows superior cycling performance of 4000 cycles at -40 °C with 95.7% capacity retention. This work elucidates the correlation between the anion effect and the thermodynamic transition of the electrolyte, offering a novel approach for designing low-temperature electrolytes.

Sustainable Aqueous Batteries Based on Bipolar Dissociation of Aluminum Hydroxyacetate Electrolyte.

Rechargeable aqueous batteries are potential systems for large-scale energy storage due to their high safety and low cost. However, developing aqueous batteries with high sustainability, affordability, and reversibility is urgent and challenging. Here we report an amphoteric aluminum hydroxyacetate (AlAc(OH)2) electrolyte with the ability of bipolar ionization of H+ and OH-, which facilitates the redox reactions at both the anthraquinone (AQ) anode and nickel hydroxide (Ni(OH)2) cathode. The bipolar ionization ability of the AlAc(OH)2(H2O)3 solvation structure results from the strong polarization ability of Al3+ and OH-. The H+/OH- dissociation ability with a dissociation constant of 5.0/3.0 is stronger than that of water (14.0), which boosts the simultaneous stable redox reactions of electrodes. Specifically, H+ uptake prevents the AQ anode from the formation of an ionic bond, suppressing the electrode dissolution, whereas OH- provides the local alkaline environment for the stable conversion reaction of the Ni(OH)2 cathode. The AQ anode in the designed AQ||Ni(OH)2 battery delivers a discharge capacity of 243.9 mAh g-1 and a capacity retention of 78.2% after 300 cycles with high reversibility. Moreover, a pouch cell with a discharge capacity of 0.90 Ah was assembled, exhibiting an energy density of 44.7 Wh kg-1 based on the total mass of the battery. This work significantly widens the types of aqueous batteries and represents a design philosophy of bipolar electrolytes and distinct electrochemical reactions with H+ and OH-.

Unveiling the Role of Fluorination in Hexacyclic Coordinated Ether Electrolytes for High-Voltage Lithium Metal Batteries.

Fluorinated ethers have become promising electrolyte solvent candidates for lithium metal batteries (LMBs) because they are endowed with high oxidative stability and high Coulombic efficiencies of lithium metal stripping/plating. Up to now, most reported fluorinated ether electrolytes are -CF3-based, and the influence of ion solvation in modifying degree of fluorination has not been well-elucidated. In this work, we synthesize a hexacyclic coordinated ether (1-methoxy-3-ethoxypropane, EMP) and its fluorinated ether counterparts with -CH2F (F1EMP), -CHF2 (F2EMP), or -CF3 (F3EMP) as terminal group. With lithium bis(fluorosulfonyl)imide as single salt, the solvation structure, Li-ion transport behavior, lithium deposition kinetics, and high-voltage stability of the electrolytes were systematically studied. Theoretical calculations and spectra reveal the gradually reduced solvating power from nonfluorinated EMP to fully fluorinated F3EMP, which leads to decreased ionic conductivity. In contrast, the weakly solvating fluorinated ethers possess higher Li+ transference number and exchange current density. Overall, partially fluorinated -CHF2 is demonstrated as the desired group. Further full cell testing using high-voltage (4.4 V) and high-loading (3.885 mAh cm-2) LiNi0.8Co0.1Mn0.1O2 cathode demonstrates that F2EMP electrolyte enables 80% capacity retention after 168 cycles under limited Li (50 µm) and lean electrolyte (5 mL Ah-1) conditions and 129 cycles under extremely lean electrolyte (1.8 mL Ah-1) and the anode-free conditions. This work deepens the fundamental understanding on the ion transport and interphase dynamics under various degrees of fluorination and provides a feasible approach toward the design of fluorinated ether electrolytes for practical high-voltage LMBs.

L-ascorbyl-2-phosphate alleviates white matter injury caused by chronic hypoxia through the PRMT5/P53/NF-κB pathway.

White matter injury (WMI) is one of the most serious complications associated with preterm births. Damage to oligodendrocytes, which are the key cells involved in WMI pathogenesis, can directly lead to myelin abnormalities. L-ascorbyl-2-phosphate (AS-2P) is a stable form of vitamin C. This study aimed to explore the protective effects of AS-2P against chronic hypoxia-induced WMI, and elucidate the underlying mechanisms. An in vivo chronic hypoxia model and in vitro oxygen-glucose deprivation (OGD) model were established to explore the effects of AS-2P on WMI using immunofluorescence, immunohistochemistry, western blotting, real-time quantitative polymerase chain reaction, Morris water maze test, novel object recognition test, beaming-walking test, electron microscopy, and flow cytometry. The results showed that AS-2P resulted in the increased expression of MBP, Olig2, PDGFRα and CC1, improved thickness and density of the myelin sheath, and reduced TNF-α expression and microglial cell infiltration to alleviate inflammation in the brain after chronic hypoxia. Moreover, AS-2P improved the memory, learning and motor abilities of the mice with WMI. These protective effects of AS-2P may involve the upregulation of protein arginine methyltransferase 5 (PRMT5) and downregulation of P53 and NF-κB. In conclusion, our study demonstrated that AS-2P attenuated chronic hypoxia-induced WMI in vivo and OGD-induced oligodendrocyte injury in vitro possibly by regulating the PRMT5/P53/NF-κB pathway, suggesting that AS-2P may be a potential therapeutic option for WMI.

FTO promotes the progression of retinoblastoma through YTHDF2-dependent N6-methyladenosine modification in E2F3.

Early treatment of retinoblastoma (RB) has significantly improved clinical outcomes. N6-methyladenosine (m6A) methylation is crucial for cancer progression. Thus, we investigated the role of FTO-dependent demethylation in RB and its underlying mechanisms. The biological behavior of RB cells was analyzed using cell counting kit-8, colony formation analysis, transwell assay, flow cytometry, and western blot analysis. m6A modification was evaluated using methylated RNA immunoprecipitation and dual-luciferase reporter assays, and E2F3 stability was assessed using Actinomycin D. The roles of FTO and E2F3 were also elucidated in vivo. These results indicated that FTO was highly expressed in RB cells with low m6A levels. FTO knockdown inhibited RB cell growth, migration, invasion, and epithelial-mesenchymal transition and arrested the cell cycle at the G0/G1 phase. Mechanistically, FTO interference promoted m6A methylation of E2F3, which was recognized by YTHDF2, thereby reducing mRNA stability. E2F3 overexpression partially rescued the effects of FTO knockdown on biological behavior. Moreover, FTO knockdown reduced tumor weight, tumor volume, ki67 expression, and tumor cell infiltration by mediating E2F3. Taken together, FTO silencing inhibited the malignant processes of RB by suppressing E2F3 in an m6A-YTHD2-dependent manner. These findings suggest that FTO is a novel therapeutic target for RB.

A quick and effective method for thermostability differentiation in cucumber (Cucumis sativus L.).

High temperature affects the growth and production of cucumber. Selecting thermotolerant cucumber cultivars is conducive to coping with high temperatures and improving production. Thus, a quick and effective method for screening thermotolerant cucumber cultivars is needed. In this study, four cucumber cultivars were used to identify heat resistance indexes. The morphological, physiological and biochemical indexes were measured. When exposed to high temperatures, thermotolerant cucumber had a more stable photosystem, membrane, and oxidation-reduction systems. The impact of high temperatures on plants is multifaceted, and the accurate discrimination of heat resistance cannot be achieved solely based on a single or multiple indicators. Therefore, principal component analysis (PCA) was employed to comprehensively evaluate the heat resistance of cucumber plants. The results showed that the heat resistance obtained by PCA was significantly correlated with the heat injury index. In addition, the stepwise regression equation identified two heat-related indices, hydrogen peroxide content (H2 O2 ) and photosynthetic operating efficiency (Fq'/Fm'), and they can quickly distinguish the heat resistance of the other 8 cucumber cultivars. These results will help to accelerate the selection of thermotolerant resources and assist in cucumber breeding.

Incommensurate Spiral Spin Order in CaMn2Bi2 Observed via High-Pressure Neutron Diffraction.

High-pressure neutron diffraction is employed to investigate the magnetic behavior of CaMn2Bi2 in extreme conditions. In contrast to antiferromagnetic ordering on Mn atoms reported at ambient pressure, our results reveal that at high pressure, incommensurate spiral spin order emerges due to the interplay between magnetism on the Mn atoms and strong spin-orbit coupling on the Bi atoms: sinusoidal spin order is observed at pressures as high as 7.4 GPa. First-principles calculations with a noncollinear spin orientation demonstrate band crossing behavior near the Fermi level as a result of strong hybridization between the d orbitals of Mn and the p orbitals of Bi atoms. Competing antiferromagnetic order is observed at different temperatures in the partially frustrated lattice. Theoretical models have been developed to investigate spin dynamics. This research provides a unique toolbox for conducting experimental and theoretical magnetic and spin dynamics studies of magnetic quantum materials via high-pressure neutron diffraction.

Long-Range Structural Order in a Hidden Phase of Ruddlesden-Popper Bilayer Nickelate La3Ni2O7.

The recent discovery of superconductivity in the Ruddlesden-Popper bilayer nickelate, specifically La3Ni2O7, has generated significant interest in the exploration of high-temperature superconductivity within this material family. In this study, we present the crystallographic and electrical resistivity properties of two distinct Ruddlesden-Popper nickelates: the bilayer La3Ni2O7 (referred to as 2222-phase) and a previously uncharacterized phase, La3Ni2O7 (1313-phase). The 2222-phase is characterized by a pseudo F-centered orthorhombic lattice, featuring bilayer perovskite [LaNiO3] layers interspaced by rock salt [LaO] layers, forming a repeated ...2222... sequence. Intriguingly, the 1313-phase, which displays semiconducting properties, crystallizes in the Cmmm space group and exhibits a pronounced predilection for a C-centered orthorhombic lattice. Within this structure, the perovskite [LaNiO3] layers exhibit a distinctive long-range ordered arrangement, alternating between single- and trilayer configurations, resulting in a ...1313... sequence. This report contributes to novel insights into the crystallography and the structure-property relationship of Ruddlesden-Popper nickelates, paving the way for further investigations into their unique physical properties.

Ferromagnetic Coupling in Quasi-One-Dimensional Hybrid Iron Chloride Hexagonal Perovskites.

We synthesize four novel quasi-one-dimensional organic-inorganic hybrid iron chloride compounds (CH3NH3FeCl3, CH(NH2)2FeCl3, C(NH2)3FeCl3, and C3H5N2FeCl3) and characterize their structural and magnetic properties. These materials crystallize in a hexagonal perovskite-type structure, constituting a triangular array of face-sharing iron chloride octahedra chains running along the c-axis, isolated from one another by the organic cation. Through magnetization and heat capacity measurements, we find that the intrachain coupling is weakly ferromagnetic for each variant. Importantly, this work underscores the utility of solid-state chemistry approaches in synthesizing new organic-inorganic hybrid materials.

Theory for nonlinear conductivity switching in semiconducting organic ferroelectrics.

In this work, the ferroelectric and semiconducting properties of the organic semiconducting ferroelectric benzotrithiophene tricarboxamide (BTTTA), and especially their nonlinear coupling, are theoretically investigated. BTTTA is an exponent of a small class of semiconducting organic ferroelectrics for which experiments have established a surprising polarization direction dependence of the bulk conductivity at finite fields. First, molecular dynamics (MD) simulations are used to investigate the occurrence and, under the influence of an external electric field, the inversion of the macroscopic electric dipole that forms along the axis of supramolecular columns of BTTTA. The MD results are consistent with the experimentally observed ferroelectric behavior of the material. Building on the MD results, a QM/MM scheme is used to investigate the charge carrier mobility in the quasi-1D BTTTA stacks in the linear and non-linear regimes. Indeed, at finite electric fields, a clear resistance switching effect was observed in the form of a hole mobility that is a factor ∼2 larger for antiparallel orientations of the polarization and field than for a parallel orientation. This phenomenon can be understood as a microscopic ratchet that is based on the non-equilibrium interaction between the (oriented) dipoles and the (direction of the) charge transport.

Family cumulative risk, life satisfaction, and anxiety and depression in adolescents: A developmental cascades model.

INTRODUCTION: Family cumulative risk (FCR) is predominantly regarded as an antecedent for adolescent mental health, as the prevailing perspective continues to emphasize the influential role of parents, despite recognizing the child's influence. To identify the interplay between family adversity (FCR, process-related FCR, and sociodemographic-related FCR), life satisfaction (LS), and anxiety and depression (AD), this study examined the cascade effects among these constructs. METHOD: Participants (N = 707; 52.9% male; grades 10 and 11) from four high schools in Wuhan, China, were recruited to participate, and they completed the measures in October 2018, April 2019, and November 2019. Family sociodemographic risk (e.g., single parenthood) and family process risk (e.g., low family cohesion) were simulated in the models for FCR, sociodemographic-related FCR, and process-related FCR. RESULTS: The random intercept cross-lagged panel models (RI-CLPMs) revealed a lagged effect from LS to FCR; lagged effects from LS and AD to process-related FCR at the within-person level; and significant associations between LS, AD, and family adversity at the between-person level. CONCLUSIONS: The lagged effects provide evidence for the influential child perspective and suggest that FCR and family process risk are sensitive to adolescent well-being and psychopathological symptoms. School mental health prevention and intervention programs that take a complete mental health approach to enhance children's well-being and alleviate symptoms would help prevent increases in family risk.

Enhancing Plasmonic Hot Electron Energy on Ag Surface by Amine Coordination.

Plasmonic catalysis has emerged as a promising approach to solar-chemical energy conversion. Notably, hot carriers play a decisive role in plasmonic catalysis since only when their energy matches with the LUMO or HOMO energy of the reactant molecule, can the reaction be activated. However, the hot carrier energy depends on the intrinsic physicochemical properties of the plasmonic metal substrate and the interaction with incident light. Tuning the hot carrier energy is of great significance for plasmonic catalysis but remains challenging. Here, we demonstrate that the energy of hot electrons can be significantly elevated to an unprecedented level through the coordination of amines on Ag surface. The bonding of amines and Ag reduces the work function of nanoparticles, leading to the increase of hot electron energy by 0.4 eV. This enhancement of energy promotes the cleavage of C-X (X=Cl, F) bonds upon excitation by visible light. This study provides new insights for promoting plasmonic charge transfer and enhancing the photocatalytic performance of plasmon-mediated systems.

Asymmetric Solvents Regulated Crystallization-Limited Electrolytes for All-Climate Lithium Metal Batteries.

Electrolytes that can keep liquid state are one of the most important physical metrics to ensure the ions transfer with stable operation of rechargeable lithium-based batteries at a wide temperature window. It is generally accepted that strong polar solvents with high melting points favor the safe operation of batteries above room temperatures but are susceptible to crystallization at low temperatures (≤-40 °C). Here, a crystallization limitation strategy was proposed to handle this issue. We demonstrate that, although the high melting points of ethylene sulfite (ES, -17 °C) and fluoroethylene carbonate (FEC, ≈23 °C), their mixtures can avoid crystallization at low temperatures, which can be attributed to low intermolecular interactions and altered molecular motion dynamics. A suitable ES/FEC ratio (10 % FEC) can balance the bulk and interface transport of ions, enabling LiNi0.8 Mn0.1 Co0.1 O2 ||lithium (NCM811||Li) full cells to deliver excellent temperature resilience and cycling stability over a wide temperature range from -50 °C to +70 °C. More than 66 % of the capacity retention was achieved at -50 °C compared to room temperature. The NCM811||Li pouch cells exhibit high cycling stability under realistic conditions (electrolyte weight to cathode capacity ratio (E/C)≤3.5 g Ah-1 , negative to positive electrode capacity ratio (N/P)≤1.09) at different temperatures.

Impersonating a Superconductor: High-Pressure BaCoO3, an Insulating Ferromagnet.

We report the high-pressure synthesis (6 GPa, 1200 °C) and ambient-pressure characterization of hexagonal HP-BaCoO3. The material (with a 2H crystal structure) has a short intrachain Co-Co distance of about 2.07 Å. Our magnetization investigation revealed robust diamagnetic behavior below approximately 130 K when the material was exposed to weak applied magnetic fields (10 Oe) and a distinct "half-levitation" phenomenon below that temperature, as is often observed for superconductors. Its field-dependent magnetization profile, however, unveils the characteristics of ferromagnetism, marked by a substantial magnetic retentivity of 0.22(1) µB/Co at a temperature of 2 K. Electrical resistivity measurements indicate that HP-BaCoO3 is a ferromagnetic insulator, not a superconductor.

High-Efficiency Lithium-Ion Transport in a Porous Coordination Chain-Based Hydrogen-Bonded Framework.

Fast and selective Li+ transport in solid plays a key role for the development of high-performance solid-state electrolytes (SSEs) of lithium metal batteries. Porous compounds with tunable Li+ transport pathways are promising SSEs, but the comprehensive performances in terms of Li+ transport kinetics, electrochemical stability window, and interfacial compatibility are difficult to be achieved simultaneously. Herein, we report a porous coordination chain-based hydrogen-bonded framework (NKU-1000) containing arrayed electronegative sites for Li+ transport, exhibiting a superior Li+ conductivity of 1.13 × 10-3 S cm-1, a high Li+ transfer number of 0.87, and a wide electrochemical window of 5.0 V. The assembled solid-state battery with NKU-1000-based SSE shows a high discharge capacity with 94.4% retention after 500 cycles and can work over a wide temperature range without formation of lithium dendrites, which derives from the linear hopping sites that promote a uniformly high-rate Li+ flux and the flexible structure that can buffer the structural variation during Li+ transport.

Layered Semiconductor Cr0.32Ga0.68Te2.33 with Concurrent Broken Inversion Symmetry and Ferromagnetism: A Bulk Ferrovalley Material Candidate.

The valleytronic state found in group-VI transition-metal dichalcogenides such as MoS2 has attracted immense interest since its valley degree of freedom could be used as an information carrier. However, valleytronic applications require spontaneous valley polarization. Such an electronic state is predicted to be accessible in a new ferroic family of materials, i.e., ferrovalley materials, which features the coexistence of spontaneous spin and valley polarization. Although many atomic monolayer materials with hexagonal lattices have been predicted to be ferrovalley materials, no bulk ferrovalley material candidates have been reported or proposed. Here, we show that a new non-centrosymmetric van der Waals (vdW) semiconductor Cr0.32Ga0.68Te2.33, with intrinsic ferromagnetism, is a possible candidate for bulk ferrovalley material. This material exhibits several remarkable characteristics: (i) it forms a natural heterostructure between vdW gaps, a quasi-two-dimensional (2D) semiconducting Te layer with a honeycomb lattice stacked on the 2D ferromagnetic slab comprised of the (Cr, Ga)-Te layers, and (ii) the 2D Te honeycomb lattice yields a valley-like electronic structure near the Fermi level, which, in combination with inversion symmetry breaking, ferromagnetism, and strong spin-orbit coupling contributed by heavy Te element, creates a possible bulk spin-valley locked electronic state with valley polarization as suggested by our DFT calculations. Further, this material can also be easily exfoliated to 2D atomically thin layers. Therefore, this material offers a unique platform to explore the physics of valleytronic states with spontaneous spin and valley polarization in both bulk and 2D atomic crystals.