Evidence of ferroelectricity in an antiferromagnetic vanadium trichloride monolayer.

A reduced dimensionality of multiferroic materials is highly desired for device miniaturization, but the coexistence of ferroelectricity and magnetism at the two-dimensional limit is yet to be conclusively demonstrated. Here, we used a NbSe substrate to break both the rotational and inversion symmetries in monolayer VCl and, thus, introduced exceptional in-plane ferroelectricity into a two-dimensional magnet. Scanning tunneling spectroscopy directly visualized ferroelectric domains and manipulated their domain boundaries in monolayer VCl, where coexisting antiferromagnetic order with canted magnetic moments was verified by vibrating sample magnetometer measurements.

A terahertz band multifunctional metamaterial transmission-absorption switching device based on vanadium dioxide.

In this paper, a vanadium dioxide (VO)-based terahertz device is proposed to realize the conversion between broadband absorption and broadband transmission functions, including the VO bottom layer, dielectric layer and VO pattern layer in a three-layer structure. With the change of the VO conductivity, the terahertz metamaterial device can switch between broadband absorption and broadband transmission. When the device exhibits broadband transmission, it has a high transmittance of 90% for terahertz waves in the 5.

3-D Printable Living Hydrogels as Portable Bio-energy Devices.

Harnessing engineered living materials for energy application represents a promising avenue to sustainable energy conversion and storage, with bio-batteries emerging as a pivotal direction for sustainable power supply. Whereas, the realization of miniaturized and portable bio-battery orchestrating off-the-shelf devices remains a significant challenge. Here, this work reports the development of a miniaturized and portable bio-battery using living hydrogels containing conductive biofilms encapsulated in an alginate matrix for nerve stimulation.

Well-Defined Nanostructures: Concept, Impact and Perspective.

Well-defined nanostructures (WDNSs) represent a transformative frontier in nanotechnology, enabling precise control over material properties through nanoscale engineering. The connectivity of nanoscale building blocks is increasingly critical in defining the properties and applications of WDNSs. Traditional dimensionality-based classifications provide foundational insights but overlook the delicate influence of connectivity architectures on functionality.

Enhancing the Low-Temperature Performance of Sodium-Ion Battery by Introducing Nanodiamonds in Anode Prepared from Cattail Grass.

Sodium-ion batteries (SIBs) have received much attention as ideal candidates for next-generation large-scale energy storage systems, but their performance significantly deteriorates at low temperatures, limiting their application in cold or high-altitude environments. This work presents an easier approach to improving low-temperature performance by incorporating nanodiamonds (NDs) into hard carbon anodes derived from cattail grass. The modified anode shows a larger specific surface area, offering more active sites for Na.

3D Printed Low-Tortuosity and Ultra-Thick Hierarchical Porous Electrodes for High-Performance Wearable Quasi-Solid-State Zn-VOH Batteries.

Rechargeable aqueous Zn-ion batteries have received considerable attention in energy storage systems owing to their merits of high safety, low cost, and excellent rate performance. However, the unsatisfactory areal energy density and poor cycling performance hinder their practical applications. Herein, the VO·6HO (VOH) nanosheet arrays and Zn nanoflake arrays growing on the 3D-printed reduced graphene oxide/carbon nanotubes (3DP-rGO/CNTs) microlattices employing the electrodeposition technique, and further serve as the cathode and anode for 3D-printed aqueous Zn-VOH battery, respectively.

High-Adhesive Hydrogel-Based Strain Sensor in the Clinical Diagnosis of Anterior Talofibular Ligament Sprain.

Anterior talofibular ligament (ATFL) sprain is one of the most prevalent sports-related injuries, so proper evaluation of ligament sprains is critical for treatment options. However, existing tests suffer from a lack of standardized quantitative evaluation criteria, interindividual variability, incompatible materials, or risks of infection. Although advanced medical diagnostic methods already have been using noninvasive, portable, and wearable diagnostic electronics, these devices have insufficient adhesion to accurately respond to internal body injuries.

Theoretical investigation of parallel NiO/GaP heterojunction nuclear battery with graphene layer and its time-related performance.

Betavoltaic (BV) batteries are regarded as appealing power sources due to their high energy densities and long lifetimes. However, the low efficiency and maximum output power density of conventional BV batteries due to the self-absorption effect of radioactive sources, which consist of separate beta-radioactive sources and semiconductor absorbers, limit their applications. In this work, we optimized and compared six NiO-related heterojunction nuclear batteries utilizing Monte Carlo software Geant4 and finite element analysis software COMSOL Multiphysics.

High-Throughput Computation of ab initio Raman Spectra for Two-Dimensional Materials.

Raman spectra play an important role in characterizing two-dimensional materials, as they provide a direct link between the atomic structure and the spectral features. In this work, we present an automatic computational workflow for Raman spectra using all-electron density functional perturbation theory. Utilizing this workflow, we have successfully completed the Raman spectra calculation for 3504 different two-dimensional materials, with the resultant data saved in a data repository.

Persistent- and Mechanoluminescence of Er-Doped NaYF for Multipurpose Use.

Advanced functional materials that possess both persistent luminescence (PersL) and mechanoluminescence (ML) have gained considerable attention during the past few years owing to their potential applications in many fields such as two-dimensional stress sensing, energy-saving lighting, and optical bioimaging. However, combined investigation of PersL and ML is still in its infancy. Here, the optical property of Er-doped NaYF, mainly focusing on the PersL and ML characteristic and their correlation, is studied in detail.

Multimode Thermal Gating Based on Elastic Ceramic-Carbon Nanowhisker/Nanofiber Aerogels by Strain Engineering Strategy.

The capability to regulate heat transport dynamically and reversibly within solid materials propels advancement in aerospace conditioning, battery thermal control, and energy harvesting/conversion industries. Although aerogels are known for thermal insulation properties, their constant thermal resistance induced by immutable pore structure makes them struggle to reverse-release the accumulated thermal energy. Here, we develop a nanocrystalline whisker/nanofiber aerogel (WFA) thermal gating induced by the self-catalyzed growth strategy, whose elasticity offers possibilities for dynamic thermal management.

Achieving Higher-Order Exceptional Points in a Terahertz Metasurface.

Exceptional points (EPs) are unique features of non-Hermitian systems, where eigenvalues and eigenvectors coalesce, enabling functionalities such as ultrasensitive sensing and topological energy transfer. While higher-order EPs have been studied in microdisk cavities and circuits, their realization in metasurfaces has been challenging. In this work, we demonstrate the first realization of a third-order EP (EP3) in terahertz metasurfaces by tuning the near-field interaction between three gold split-ring resonators.

Harnessing Transfer Deep Learning Framework for the Investigation of Transition Metal Perovskite Oxides with Advanced p-n Transformation Sensing Performance.

Gas sensing materials based on transition metal perovskite oxides (TMPOs) have garnered extensive attention across various fields such as air quality control, environmental monitoring, healthcare, and national defense security. To overcome challenges encountered in traditional research, a deep learning framework combining natural language processing technology (Word2Vec) and crystal graph convolutional neural network (CGCNN) was adopted in this study, proposing a predictive method that incorporates a comprehensive data set consisting of 1.2 million literature abstracts and 110,000 crystal structure data entries.

Stability of photoelectrochemical cells based on colloidal quantum dots.

Solar-driven photoelectrochemical (PEC) cells, sensitized by colloidal quantum dots (QDs), are emerging as a promising approach for solar-to-fuel conversion, including hydrogen evolution and peroxide production. The high absorption coefficient and customizable size/composition/shape of QDs can effectively enhance and broaden the light absorption capabilities of the system. Additionally, QD-based heterostructures can facilitate carrier transfer, thereby enhancing the overall performance.

An ultra-violet and infrared dual-band photodetector using a GaO thin film and HgTe colloidal quantum dots.

Dual-band photodetection of ultraviolet (UV) and infrared (IR) light is an advanced technology aimed at simultaneously or selectively detecting signals from these two distinct wavelength bands. This technique offers broad application prospects, particularly in environments requiring multispectral information. In this work, a solar-blind UV photodetector made from an amorphous GaO (a-GaO) thin film was combined with a short-wave infrared photodetector made from a HgTe colloidal quantum dot (CQD) film.

Room-Temperature Perovskite Phase Transition of CsPbI for PV Manufacturing on Flexible Substrates.

Printing perovskite films typically involves a high-temperature treatment exceeding 150 °C, which limits the manufacturing of flexible devices. All inorganic CsPbI perovskite is particularly promising for commercialization due to its high thermal stability. Herein, we discovered that when using DMF precursors containing CsI and HPbI for fabricating CsPbI films, an isopropanol (IPA) antisolvent bath immersion treatment of the wet films can enable a direct and rapid formation of optically active perovskite black phases at room temperature without annealing.

Enabling Low-Temperature Zinc-Bromine Microbatteries with an Additive-Free Electrolyte Design.

Aqueous zinc-bromine microbatteries (Zn-Br MBs) are promising energy storage devices for miniaturized electronic applications. However, their performance in low-temperature environments remains a challenge due to poor compatibility between antifreeze agents and complexing agents. In this work, we propose an additive-free electrolyte design to address this incompatibility from the source.

Operando-informed precatalyst programming towards reliable high-current-density electrolysis.

Electrocatalysts support crucial industrial processes and emerging decarbonization technologies, but their design is hindered by structural and compositional changes during operation, especially at application-relevant current densities. Here we use operando X-ray spectroscopy and modelling to track, and eventually direct, the reconstruction of iron sulfides and oxides for the oxygen evolution reaction. We show that inappropriate activation protocols lead to uncontrollable Fe oxidation and irreversible catalyst degradation, compromising stability and reliability and precluding predictive design.

Adaptive cold-atom magnetometry mitigating the trade-off between sensitivity and dynamic range.

Cold-atom magnetometers can achieve an exceptional combination of superior sensitivity and high spatial resolution. One key challenge that these quantum sensors face is improving the sensitivity within a given timeframe while preserving a high dynamic range. Here, we experimentally demonstrate an adaptive entanglement-free cold-atom magnetometry with both superior sensitivity and high dynamic range.

Gradient Sodium Deficiency Optimization in O3-Type Cathode Materials for Superior Performance and Air Stability.

O3-type layered oxides are promising cathode materials for sodium-ion batteries due to their easy synthesis and high sodium content. However, complex phase transitions and poor air stability limit their practical applications. Introducing sodium deficiency suppresses reactions with air and improves phase stability, but often at the cost of significantly compromising the sodium storage capacity.

Near-Infrared Nanothermometer Reveals Temperature Discrepancy between Organs and Body Surface for Heatstroke Prevention.

Organ temperatures often vary significantly from body surface temperatures during heatstroke, leading to acute organ failure, although body temperature is continuously controlled. However, the exact temperature discrepancy between them remains unclear due to a lack of noninvasive techniques for real-time monitoring of organ temperature fluctuations. Herein, we developed a near-infrared emissive nanothermometer by codoping Nd and Yb to produce two distinct emissions at 980 and 1330 nm under 808 nm excitation.

Energy harvesting from clothing.

Seeking new energy sources, especially those with less environmental impact, has been a consistent effort in the field of energy harvesting. In this work, we present an innovative energy harvesting technique for collecting energy from clothing. In this convenient but powerful method, electrical energy is generated by simply sliding a zein film assembly on the surface of clothes by constructing zein/cloth direct current (DC) triboelectric nanogenerators (TENGs).

Spatio-temporal analysis of urban expansion and land use dynamics using google earth engine and predictive models.

Urban expansion and changes in land use/land cover (LULC) have intensified in recent decades due to human activity, influencing ecological and developmental landscapes. This study investigated historical and projected LULC changes and urban growth patterns in the districts of Multan and Sargodha, Pakistan, using Landsat satellite imagery, cloud computing, and predictive modelling from 1990 to 2030. The analysis of satellite images was grouped into four time periods (1990-2000, 2000-2010, 2010-2020, and 2020-2030).

Realizing High Thermoelectric Performance in ZnCl-Doped N-Type Polycrystalline SnSe Through Band Engineering and Incorporating Multiple Defects.

SnSe-based compounds, as promising thermoelectric materials, are well-known for their intrinsically low thermal conductivity and outstanding thermoelectric performance. However, the suboptimal electrical transport capacity for n-type polycrystalline SnSe significantly hinders the improvement of its thermoelectric performance. In this work, an effective approach for enhancing the thermoelectric performance of n-type SnSe polycrystalline materials through ZnCl doping has been investigated.

Quantitative analysis of ferromanganese crusts (Fe-Mn crusts) using laser-induced breakdown spectroscopy combined with machine learning.

Background: Rapid and on-board elemental analysis on the mineral deposits taken from the deep seabed are of great importance for the deep-sea mineral resource survey. Traditional geochemical tools are often time-consuming that require transferring the samples from the vessel to laboratory, therefore make a quite long time for acquiring the information of the mineral deposits after taking them from the deep seabed. There is a need to develop a rapid and environmentally friendly method, which is more important for the on-board mineral analysis during the deep-sea mineral resource survey.