Lithium-ion batteries (LIBs) have dominated the market for a long time. However, the scarcity of lithium resources has sparked concerns about future energy storage devices, leading many researchers to turn their attention to other energy storage devices, such as sodium-ion batteries (SIBs), potassium-ion batteries (KIBs), zinc-ion batteries (ZIBs), and so on. Among them, SIBs have attracted widespread attention from researchers due to their abundant sodium resources, high safety, and excellent low-temperature performance. Because the cathode of the battery determines the energy density, cycle life, charge/discharge rate, and cost, the research on the cathodes for SIBs is particularly important. Layered oxide cathodes, with their periodic layered structure, good electrical conductivity, and two-dimensional ion transport channels, are regarded as the most promising cathode materials for SIBs. Currently, the main issues facing layered oxide cathodes include irreversible phase transitions, high air sensitivity, insufficient energy density, surface residual alkali, and the migration and dissolution of transition metals. The key to solving these problems lies in the development of a new generation of high-performance layered oxide cathodes. Hence, we review the current research progress of layered oxide cathode materials for SIBs and various optimizing strategies, and finally summarize and provide an outlook on the future development trends of SIBs.

Physical reservoir computing (PRC) offers an effective computing paradigm for spatiotemporal information processing with low training costs. Achieving controllable regulation over the temporal dynamics of devices to meet the computational demands of each physical layer is a key challenge for realizing high-performance PRC chips. Here, we proposed a homogeneously integrated all-PRC with tunable temporal dynamics. Utilizing the modulation effect of oxygen vacancies on the energy barrier of the pentacene/ZnO interface, short-term memory, and long-term memory switching characteristics have been achieved within the same device structure. Furthermore, by altering the gate voltage, the reservoir exhibited a broad range ratio of temporal characteristics (>10²), which provides the potential to map information with different temporal characteristics. Inspired by the process of encoding and reconstructing spatiotemporal information in the human visual system, a biomimetic obstacle recognition system has been constructed to assist visually impaired individuals in walking, demonstrating excellent accuracy in obstacle types (100%) and distances (97.2%) recognition. This work offers a promising avenue for the development of an integrated PRC system with multi-timescale information processing capability.

Wavelength selective imaging has a wide range of applications in image recognition and other application scenarios, which can effectively improve the recognition rate of objects. However, in the existing technical scenarios, it is usually necessary to use complex optical devices such as filters or gratings to achieve wavelength extraction. These methods inevitably bring about the problems of complex structure and low integration. Therefore, it is necessary to realize the wavelength extraction function at the device level. Here, we realize the wavelength extraction function and wide-spectrum imaging function in the visible to infrared band based on a visible light absorber/floating gate storage layer/near-infrared (NIR) photogating layer configuration. Under infrared irradiation, the device exhibits negative photoresponse through the absorption of infrared light by the Ge substrate and the photogating effect, and realizes visible positive light response through the absorption of visible light by MoS₂. Utilizing the memory function of the device, by cleverly changing the gate voltage pulse, the photoresponse state of the output voltage is effectively adjusted to achieve three imaging states: visible light response only, response to both visible and infrared light, and infrared light response only. Active selective imaging of the word “XDU” was achieved at 532 and 1550 nm wavelength. By using the photoresponse data of the device, the passive imaging of the topography of Xi'an, Shaanxi Province was obtained, which effectively improves the recognition rate of mountains and rivers. The proposed reconfigurable visible–infrared wavelength-selective imaging photodetector can effectively extract image information and improve the image recognition rate while ensuring a simple structure. The single-chip-based spectral separation imaging solution lays a good foundation for the further development of visible–infrared vision applications.

Respiratory muscle training can improve respiratory function by strengthening muscle mass, which is of great help to populations with respiratory system diseases and athletes. Existing respiratory muscle training methods rely on resistance that hinders breathing, and the resistance cannot be adjusted automatically. However, the detection of the user's current muscle fatigue state and precise adjustment of resistance during respiratory muscle training are crucial to training efficiency. Here, we have developed a hybrid sensor that combines a triboelectric nanogenerator and a piezoelectric nanogenerator. This hybrid sensor can simultaneously collect both high-frequency and low-frequency signals generated by the Karman vortex street effect with low hysteresis. When the airway height is 30 mm, the sensor size is 52 μm × 40 mm × 17 mm, the output performance of the sensor is optimal, and the minimum response amplitude for the sensor is approximately 3 mm. Under normal breathing conditions, the output peak voltage is 7 V, the current is 100 μA, the charge transfer amount generated by one movement is 55 nC, the response time is 0.16 s, and the sensitivity is 0.07 V/m·s^–1. With the help of the principal component analysis algorithm, features related to the fatigue state of muscles were extracted from the collected signals, and the accuracy rate can reach 94.4%. Subsequently, the stepper motor will rotate to adjust the resistance appropriately. We fused the hybrid sensor, machine learning, control circuits, and stepper motors and fabricated a resistance self-adaptation program. Our findings inspire researchers in the field of rehabilitation and sports training to evaluate training status and improve training efficiency.

Various forms of intelligent light-controlled soft actuators and robots rely on advanced material architectures and bionic systems to enable programmable remote actuation and multifunctionality. Despite advancements, significant challenges remain in developing actuators and robots that can effectively mimic the low-intensity, wide-wavelength light signal sensing and processing functions observed in living organisms. Herein, we report a design strategy that integrates light-responsive artificial synapses (AS) with liquid crystal networks (LCNs) to create bionic light-controlled LCN soft actuators (AS-LCNs). Remarkably, AS-LCNs can be controlled with light intensities as low as 0.68 mW cm^–2, a value comparable to the light intensity perceivable by the human eye. These AS-LCNs can perform programmable intelligent sensing, learning, and memory within a wide wavelength range from 365 nm to 808 nm. Additionally, our system demonstrates time-related proofs of concept for a tachycardia alarm and a porcupine defense behavior simulation. Overall, this work addresses the limitations of traditional light-controlled soft actuators and robots in signal reception and processing, paving the way for the development of intelligent soft actuators and robots that emulate the cognitive abilities of living organisms.

Metallizing 2D semiconductors is a crucial research area with significant applications, such as reducing the contact resistance at metal/2D semiconductor interfaces. This is a key challenge in the realization of next-generation low-power and high-performance devices. While various methods exist for metallizing Mo- and W-based 2D semiconductors like MoS₂ and WSe₂, effective approaches for Pt-based ones have been lacking. This study demonstrates that platinum dichalcogenides (PtX₂, X = Se or Te) undergo a semiconductor-to-metal transition when grown on niobium dichalcogenides (NbX₂, X = Se or Te). PtX₂/NbX₂ heterostructures were fabricated using molecular beam epitaxy (MBE) and characterized by Raman spectra, scanning transmission electron microscopy (STEM) and scanning tunneling microscopy/spectroscopy (STM/STS). Raman spectra and STEM confirm the growth of 1T-phase PtX₂ and 1H-phase NbX₂. Both 2D STS mapping and layer-dependent STS show that regardless of their layer numbers, both pristine semiconducting PtSe₂ and PtTe₂ are converted to metallic forms when interfacing with NbSe₂ or NbTe₂. Density functional theory (DFT) calculations suggest that the metallization of PtSe₂ on NbX₂ and PtTe₂ on NbTe₂ results from interfacial orbital hybridization, while for PtTe₂ on NbSe₂, it is due to the strong p-doping effect caused by interfacial charge transfer. Our work provides an effective method for metallizing PtX₂ semiconductors, which may lead to significant applications such as reducing the contact resistance at metal electrode/2D semiconductor interfaces and developing devices like rectifiers, rectenna, and photodetectors based on 2D Schottky diodes.

MXenes, a class of two-dimensional (2D) transition metal carbides, and covalent organic frameworks (COFs) deliver unique structural and electrochemical properties, making them promising candidates for energy storage and conversion applications. MXenes exhibit excellent conductivity and tunable surface chemistries, whereas the COFs provide high porosity and structural versatility. Recent advances in integrating MXene-COF composites have revealed their potential to enhance charge transfer and energy storage/conversion properties. The work highlights key developments in MXene-COF integration, offering insights into their applications in batteries (Li-ion, K-ion, Na-ion, and Li-S), supercapacitors, and electrocatalysis (HER, OER, RR, NRR, and ORRCO2), while also addressing current challenges and future directions for not only energy conversion but also other electronic devices.

Considering sustainable development factors such as element abundance, cost, environmental friendliness, and stability, the research and development of novel inorganic non-lead perovskites are very significant. Copper-silver-bismuth iodide (CABI) is a promising solar cell material with halide perovskite genes, possessing eco-friendly, element-rich, and cost-effective characteristics. The fabrication of high-quality CABI films with tailored compositions still poses a substantial hurdle. We developed a CuAgBi₂I₈ material that effectively reduced the bandgap to 1.69 eV by optimizing Bi distribution to create an environment conducive to in-situ redox reactions of Bi with I₂, Cu, and Ag via vapor-phase synthesis. This strategy proved highly effective in synthesizing high-quality CuAgBi₂I₈ compound, accompanied by significant improvements in film quality, including enhanced crystallinity, minimized defects, and reduced non-radiative recombination. The crystal structure of CuAgBi₂I₈ and mechanisms of elemental reactions and diffusion are discussed. Devices featuring the structure FTO/c-TiO₂/m-TiO₂/CuAgBi₂I₈/CuI/Spiro-OMeTAD/carbon achieved a champion efficiency of 3.21%, the highest for CABI solar cells. This work provides a novel idea and approach to governing the gas–solid element diffusion and reaction for high-quality CABI and related halide perovskite films.

Bioinspired soft robots hold great potential to perform tasks in unstructured terrains. Ferroelectric polymers are highly valued in soft robots for their flexibility, lightweight, and electrically controllable deformation. However, achieving large strains in ferroelectric polymers typically requires high driving voltages, posing a significant challenge for practical applications. In this study, we investigate the role of crystalline domain size in enhancing the electrostrain performance of the relaxor ferroelectric polymer poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene-fluorinated alkynes) (P(VDF-TrFE-CFE-FA)). Leveraging its remarkable inverse piezoelectric coefficient (|d₃₃*| = 701 pm V^–1), we demonstrate that the planar films exhibit a five times larger bending angle than that of commercial PVDF films at low electric fields. Based on this material, we design a petal-structured soft robot that achieves a curvature of up to 4.5 cm^–1 at a DC electric field of 30 V μm^–1. When integrated into a bipedal soft robot, it manifests outstanding electrostrain performance, achieving rapid locomotion of ~19 body lengths per second (BL s^–1) at 10 V μm^–1 (560 Hz). Moreover, the developed robot demonstrates remarkable abilities in climbing slopes and carrying heavy loads. These findings open new avenues for developing low-voltage-driven soft robots with significant promise for practical applications.