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The anomalous Hall effect (AHE) that associated with the Berry curvature of occupied electronic states in momentum-space is one of the intriguing aspects in condensed matter physics, and provides an alternative for potential applications in topological electronics. Previous experiments reported the tunable Berry curvature and the resulting magnetization switching process in the AHE based on strain engineering or chemical doping. However, the AHE modulation by these strategies are usually irreversible, making it difficult to realize switchable control of the AHE and the resultant spintronic applications. Here, we demonstrated the switchable control of the Berry-curvature-related AHE by electrical gating in itinerant ferromagnetic Cr₇Te₈ with excellent ambient stability. The gate-tunable sign reversal of the AHE can be attributed to the redistribution of the Berry curvature in the band structure of Cr₇Te₈ due to the intercalation-induced change in the Fermi level. Our work facilitates the applications of magnetic switchable devices based on gate-tunable Berry curvature.

Accurately forecasting the nonlinear degradation of lithium-ion batteries (LIBs) using early-cycle data can obviously shorten the battery test time, which accelerates battery optimization and production. In this work, a self-adaptive long short-term memory (SA-LSTM) method has been proposed to predict the battery degradation trajectory and battery lifespan with only early cycling data. Specifically, two features were extracted from discharge voltage curves by a time-series-based approach and forecasted to further cycles using SA-LSTM model. The as-obtained features were correlated with the capacity to predict the capacity degradation trajectory by generalized multiple linear regression model. The proposed method achieved an average online prediction error of 6.00% and 6.74% for discharge capacity and end of life, respectively, when using the early-cycle discharge information until 90% capacity retention. Furthermore, the importance of temperature control was highlighted by correlating the features with the average temperature in each cycle. This work develops a self-adaptive data-driven method to accurately predict the cycling life of LIBs, and unveils the underlying degradation mechanism and the importance of controlling environmental temperature.

Transition metal dichalcogenides (TMDs) are a promising candidate for developing advanced sensors, particularly for day and night vision systems in vehicles, drones, and security surveillance. While traditional systems rely on separate sensors for different lighting conditions, TMDs can absorb light across a broad-spectrum range. In this study, a dual vision active pixel image sensor array based on bilayer WS₂ phototransistors was implemented. The bilayer WS₂ film was synthesized using a combined process of radio-frequency sputtering and chemical vapor deposition. The WS₂-based thin-film transistors (TFTs) exhibit high average mobility, excellent I_on/I_off, and uniform electrical properties. The optoelectronic properties of the TFTs array exhibited consistent behavior and can detect visible to near-infrared light with the highest responsivity of 1821 A W⁻¹ (at a wavelength of 405 nm) owing to the photogating effect. Finally, red, green, blue, and near-infrared image sensing capabilities of active pixel image sensor array utilizing light stencil projection were demonstrated. The proposed image sensor array utilizing WS₂ phototransistors has the potential to revolutionize the field of vision sensing, which could lead to a range of new opportunities in various applications, including night vision, pedestrian detection, various surveillance, and security systems.

Quantitative analysis of gait parameters, such as stride frequency and step speed, is essential for optimizing physical exercise for the human body. However, the current electronic sensors used in human motion monitoring remain constrained by factors such as battery life and accuracy. This study developed a self-powered gait analysis system (SGAS) based on a triboelectric nanogenerator (TENG) fabricated electrospun composite nanofibers for motion monitoring and gait analysis for regulating exercise programs. The SGAS consists of a sensing module, a charging module, a data acquisition and processing module, and an Internet of Things (IoT) platform. Within the sensing module, two specialized sensing units, TENG-S1 and TENG-S2, are positioned at the forefoot and heel to generate synchronized signals in tandem with the user's footsteps. These signals are instrumental for real-time step count and step speed monitoring. The output of the two TENG units is significantly improved by systematically investigating and optimizing the electrospun composite nanofibers' composition, strength, and wear resistance. Additionally, a charge amplifier circuit is implemented to process the raw voltage signal, consequently bolstering the reliability of the sensing signal. This refined data is then ready for further reading and calculation by the micro-controller unit (MCU) during the signal transmission process. Finally, the well-conditioned signals are wirelessly transmitted to the IoT platform for data analysis, storage, and visualization, enhancing human motion monitoring.

The recent progress on the liquid crystalline (LC) dispersion of two-dimensional (2D) transition metal carbides (MXenes) has propelled this unique nanomaterial into a realm of high-performance architectures, such as films and fibers. Additionally, compared to architectures made from typical non-LC dispersions, those derived from LC MXene possess tunable ion transport routes and enhanced conductivity and physical properties, demonstrating great potential for a wide range of applications, such as electronic displays, smart glasses, and thermal camouflage devices. This review provides an overview of the progress achieved in the production and processing of LC MXenes, including critical discussions on satisfying the required conditions for LC formation. It also highlights how acquiring LC MXenes has broadened the current solution-based manufacturing paradigm of MXene-based architectures, resulting in unprecedented performances in their conventional applications (e.g., energy storage and strain sensing) and in their emerging uses (e.g., tribology). Opportunities for innovation and foreseen challenges are also discussed, offering future research directions on how to further benefit from the exciting potential of LC MXenes with the aim of promoting their widespread use in designing and manufacturing advanced materials and applications.

High-voltage nickel (Ni)-rich layered oxide-based lithium metal batteries (LMBs) exhibit a great potential in advanced batteries due to the ultra-high energy density. However, it is still necessary to deal with the challenges in poor cyclic and thermal stability before realizing practical application where cycling life is considered. Among many improved strategies, mechanical and chemical stability for the electrode electrolyte interface plays a key role in addressing these challenges. Therefore, extensive effort has been made to address the challenges of electrode-electrolyte interface. In this progress, the failure mechanism of Ni-rich cathode, lithium metal anode and electrolytes are reviewed, and the latest breakthrough in stabilizing electrode-electrolyte interface is also summarized. Finally, the challenges and future research directions of Ni-rich LMBs are put forward.

Protonic solid oxide electrolysis cells (P-SOECs) operating at intermediate temperatures, which have low costs, low environmental impact, and high theoretical electrolysis efficiency, are considered promising next-generation energy conversion devices for green hydrogen production. However, the developments and applications of P-SOECs are restricted by numerous material- and interface-related issues, including carrier mismatch between the anode and electrolyte, current leakage in the electrolyte, poor interfacial contact, and chemical stability. Over the past few decades, considerable attempts have been made to address these issues by improving the properties of P-SOECs. This review comprehensively explores the recent advances in the mechanisms governing steam electrolysis in P-SOECs, optimization strategies, specially designed components, electrochemical performance, and durability. In particular, given that the lack of suitable anode materials has significantly impeded P-SOEC development, the relationships between the transferred carriers and the cell performance, reaction models, and surface decoration approaches are meticulously probed. Finally, the challenges hindering P-SOEC development are discussed and recommendations for future research directions, including theoretical calculations and simulations, structural modification approaches, and large-scale single-cell fabrication, are proposed to stimulate research on P-SOECs and thereby realize efficient electricity-to-hydrogen conversion.

Finding a real thermoelectric (TE) material that excels in various aspects of TE performance, mechanical properties, TE power generation, and cooling is challenging for its commercialization. Herein, we report a novel multifunctional Ge_0.78Cd_0.06Pb_0.1Sb_0.06Te material with excellent TE performance and mechanical strength, which is utilized to construct candidate TE power generation and cooling devices near room temperature. Specifically, the effectiveness of band convergence, combined with optimized carrier concentration and electronic quality factor, distinctly boosts the Seebeck coefficient, thus greatly improving the power factor. Advanced electron microscopy observation indicates that complex multi-scale hierarchical structures and strain field distributions lead to ultra-low lattice thermal conductivity, and also effectively enhance mechanical properties. High ZT ~ 0.6 at 303 K, average ZT_ave ~ 1.18 from 303 to 553 K, and Vickers hardness of ~200 H_v in Ge_0.78Cd_0.06Pb_0.1Sb_0.06Te are obtained synchronously. Particularly, a 7-pair TE cooling device with a maximum ΔT of ~45.9 K at T_h = 328 K, and a conversion efficiency of ~5.2% at T_h = 553 K achieving in a single-leg device. The present findings demonstrate a unique approach to developing superior multifunctional GeTe-based alloys, opening up a promising avenue for commercial applications.

All solid-state batteries (ASSBs) are the holy grails of rechargeable batteries, where extensive searches are ongoing in the pursuit of ideal solid-state electrolytes. Nevertheless, there is still a long way off to the satisfactorily high (enough) ionic conductivity, long-term stability and especially being able to form compatible interfaces with the solid electrodes. Herein, we have explored ionic transport behavior and high mobility in the sub-nano pore networks in the framework structures. Macroscopically, the frameworked electrolyte behaves as a solid, and however in the (sub)-nano scales, the very limited number of solvent molecules in confinement makes them completely different from that in liquid electrolyte. Differentiated from a liquid-electrolyte counterpart, the interactions between the mobile ions and surrounding molecules are subject to dramatic changes, leading to a high ionic conductivity at room temperature with a low activation energy. Li⁺ ions in the sub-nano cages of the network structure are highly mobile and diffuse rather independently, where the rate-limiting step of ions crossing cages is driven by the local concentration gradient and the electrostatic interactions between Li⁺ ions. This new class of frameworked electrolytes (FEs) with both high ionic conductivity and desirable interface with solid electrodes are demonstrated to work with Li-ion batteries, where the ASSB with LiFePO₄ shows a highly stable electrochemical performance of over 450 cycles at 2°C at room temperature, with an almost negligible capacity fade of 0.03‰ each cycle. In addition, the FE shows outstanding flexibility and anti-flammability, which are among the key requirements of large-scale applications.

Pathogenic and corrosive bacteria pose a significant risk to human health or economic well-being. The specific, sensitive, and on-site detection of these bacteria is thus of paramount significance but remains challenging. Taking inspiration from immunoassays with primary and secondary antibodies, we describe here a rational design of microbial sensor (MS) under a dual-specificity recognition strategy using Pseudomonas aeruginosa (P. aeruginosa) as the detection model. In the MS, engineered aptamers are served as the primary recognition element, while polydopamine-N-acetyl-D-galactosamine (PDA-Gal NAc) nanoparticles are employed as the secondary recognition element, which will also generate and amplify changes in the output voltage signal. To achieve self-powering capability, the MS is constructed based on a triboelectric nanogenerator (TENG) with the specific aptamers immobilized on the TENG electrode surface. The as-prepared MS-TENG system exhibits good stability in output performance under external forces, and high specificity toward P. aeruginosa, with no cross-reactivity observed. A linear relationship (R² = 0.995) between the output voltage and P. aeruginosa concentration is established, with a limit of detection estimated at around 8.7 × 10³ CFU mL⁻¹. The utilization of PDA-Gal NAc nanoparticles is found to play an important role in enhancing the specific and reliability of detection, and the underlying mechanisms are further clarified by computational simulations. In addition, the MS-TENG integrates a wireless communication module, enabling real-time monitoring of bacterial concentration on mobile devices. This work introduces a pioneering approach to designing self-powered smart microbial sensors with high specificity, using a double recognition strategy applicable to various bacteria beyond P. aeruginosa.