Tracking dynamic ion diffusion in electrode materials has long posed a significant challenge in battery performance research. The development of facile visualization techniques to reveal ion transport dynamics enables more intuitive and in-depth understanding of degradation mechanisms. In this study, we introduce an in situ optical electrochemical characterization method for organic single-crystal electrode materials. By leveraging the electrochemical-responsive optical properties of these materials, we successfully visualized the dynamic ion diffusion process within organic single-crystal electrodes. Using this approach, we identified a reaction-coupled ion diffusion mechanism governed by Fick's first law. Our results reveal strong crystal-plane-dependent diffusion characteristics and demonstrate that reaction-induced conductivity enhancement is a key factor enabling high-rate performance. Furthermore, the method vividly captures ion-intercalation-induced volume expansion and active material dissolution/shuttling phenomena. This methodology provides fundamental insights into the kinetic behavior and degradation mechanisms of organic electrode systems and demonstrates broad applicability to other material systems.

Developing two-dimensional (2D) transition metal dichalcogenides (TMDs) that possess uniform crystal orientation and controlled interlayer stacking is essential for next-generation electronic and quantum devices. However, precise control over both lattice alignment and stacking polytype in materials like NbSe2 remains challenging, primarily due to the small energy difference favoring the hexagonal (H)-stacked phase and the significant lattice mismatch with conventional substrates. Here, we demonstrate the successful growth of mono-oriented rhombohedral-stacked (R-stacked) NbSe2 ribbons on c-plane sapphire substrates via step-guided epitaxy. This approach utilizes the interaction between atomic steps on the sapphire surface and the NbSe2 layers: the steps control the orientation and stacking of the NbSe2 layers. Combined experimental and theoretical analyses reveal that these atomic steps simultaneously guide unidirectional alignment and stabilize the R-stacking configuration. The synthesized NbSe2 ribbons exhibit promising superconducting properties, with a superconducting transition temperature of 5.6 K and a residual resistance ratio of 4.5. This work paves the way for large-scale integration of single-crystal R-stacked NbSe2 ribbons, holding immense potential for future applications in superconducting electronics and beyond.

In recent years, effective carrier-exciton conversion and defect engineering in tunneling diodes based on metal-insulator-semiconductor (MIS) van der Waals heterostructures have attracted extensive research interest in modulating optoelectronic device performance. Effectively exciting and controlling defects in such devices, thereby enabling tunable optoelectronic responses, is critical for both functional realization and performance enhancement. Here, we report a MIS heterostructure photodetector consisting of monolayer graphene (Gr), hexagonal boron nitride (h-BN), and monolayer molybdenum disulfide (MoS2). Defect states within h-BN layers are successfully activated, allowing controlled interlayer charge transfer among the two-dimensional materials. Under visible-light illumination, the device reveals a wavelength-selective photoresponse at 405 and 638 nm. The mechanism underlying the selective photocurrent generation is elucidated through defect-state modeling of h-BN combined with energy-band alignment analysis. Notably, the device demonstrates a high switching ratio of up to 105 and an ultrafast response time of approximately 7-8 μs. These characteristics enable the demonstration of its potential for applications such as raster-scanned photocurrent imaging and optoelectronic logic operations.

ABSTRACT Edge vision systems frequently require the seamless integration of sensing, processing, and encryption within a unified hardware platform, yet conventional approaches often rely on dynamic electrical gating or physically separated modules, which may introduce potential side‐channel risks and expose intermediate data. Here, we demonstrate that a PtSe 2 /MoTe 2 van der Waals (vdW) heterostructure under fixed gate bias produces a bipolar pulsed photocurrent within each optical cycle through concurrent photovoltaic (PV) and photothermoelectric (PTE) effects. Critically, this temporal‐domain transient signal simultaneously serves two distinct functions. Its signed components act as hardware‐measured weights for software‐configurable multispectral image processing, while these same weights provide a hardware‐derived seed material for key generation, a concept termed “kernel‐as‐key.” Using this unified framework, we implement a simulation of multispectral convolution processing (MCP) and data encryption without requiring dynamic electrical reconfiguration. This work introduces a temporal‐domain photoresponse scheme that offers a promising hardware primitive, providing a possible pathway toward enhanced security in edge vision architectures by reducing the need for dynamic electrical reconfiguration and minimizing the exposure of intermediate processed data.

Color filters are extensively applied in the fields of display and lighting. Although various color filters have been designed to date, very few studies have been devoted to dynamic color filtering that can enable a wealth of advanced functionalities. Herein, we demonstrate a dynamic color filter based on the optical interference of Fabry-Pérot (F-P) and actively tunable optical properties of vanadium dioxide (VO2). The color filter is constructed by sputtering a VO2 film on a polished Al sheet, exhibiting a continuum of customized colors depending on the VO2 thickness. Dynamic color filtering is promoted by the insulator-metal transition (IMT) of VO2, enabling not only the generation of two distinct color states but also the realization of continuous color modulation. Additionally, this filter exhibits tunable broadband near-perfect absorption in the visible and near-infrared regions. Upon VO2 phase transition, the absorption peak can be modulated across a large spectral range, and the absorption intensity at a specific wavelength can be switched with a large on-off ratio, and the largest absorption contrast and modulation depth (MD) reach ∼63.1% and ∼4.8 dB, respectively. Benefiting from the dynamically tunable optical properties, a temperature perception device and wavelength-selective dynamic absorber are demonstrated, revealing the great potential of such a device for applications in color decoration, temperature sensing, adaptive optical camouflage, optical switches, etc. The structurally simple, photolithography-free, and scalable fabrication processes provide great convenience for low-cost and robust optoelectronic devices based on color filters.

Momentum-resolved spin textures and potential valley-contrasting physical properties in the momentum space are two intriguing characteristics of noncentrosymmetric materials, and they have broad applications in spintronics and valleytronics. The realization of diverse spin textures within a single material, along with their further coupling to the valley degree of freedom, is highly desirable. Via first-principles calculations, we investigate electronic properties of Janus MP_2S_3Se_3 monolayers, which exhibits distinct spin textures at different valleys. While Ising-type spin textures are located at K_± valleys, the symmetry breaking from the Janus structure brings about a coexistence of Weyl-type and Rashba-type spin textures at Γ valley. In addition to valley-contrasting spin textures, valley dependence also occurs in Berry-curvature-driven anomalous Hall currents and optical selectivity. Besides, energy differences between Γ and K_±, as well as band gaps, are highly tunable by applied strain. These findings present an intriguing coupling between diverse spin textures and multiple valleys, and pave the way for designing advanced electronic devices that leverage spin and valley degrees of freedom.

Graphitic carbon nitride, with its intrinsic nitrogen-rich framework and extended π-conjugated electronic structure, has emerged as a versatile support matrix for anchoring metal-based active sites. In this study, a series of monometallic and bimetallic copper-zinc catalysts with tunable copper/zinc molar ratios, supported on graphitic carbon nitride featuring a distinct wrinkled and porous structure, were synthesized. At a copper/zinc molar ratio of 1:1, the as-prepared catalyst, denoted as copper-zinc–graphitic carbon nitride (1:1), maximized the exposure of accessible active sites and accelerated mass transport of reactants and products, which were critical factors for boosting the kinetics of the carbon dioxide reduction reaction. Copper-zinc-graphitic carbon nitride (1:1) exhibited the highest current response, the smallest Tafel slope, and the largest electrochemical active surface area. At a potential of − 0.95 V versus the reversible hydrogen electrode, this bimetallic catalyst achieved remarkable Faradaic efficiencies of 50.2

Two-dimensional MoS2 is a promising material for applications in energy conversion or light harvesting, but the weak light absorption by monolayer MoS2 hinders its direct application in devices. To enhance the absorption of MoS2, various strategies have been developed based on metal-semiconductor heterostructures, where multiple processes can be effective, depending on subtle local nanoscale parameters. Revealing key factors in such processes requires characterization on single heterostructures, at the micro- or even nanoscale. We present direct photocurrent mapping (PCM) on single Au nanoplate/MoS2 heterostructures inside a photoelectrochemical cell, which reveals intense photocurrent signal at the nanoplate edges. The Au nanoplate/MoS2/TiO2 heterostructure exhibits a better performance in comparison to MoS2/Au nanoplate/TiO2 structure, achieving maximum photocurrent performance of 32.8 nA under 600 nm excitation wavelength, which represents an enhancement factor of 32x due to the heterostructure. Our PCM measurements indicate that maximum performance is achieved at different excitation wavelengths for varying excitation power, with a transition from a linear power dependence at long excitation wavelengths to superlinear dependence at short excitation wavelengths. A thorough theoretical analysis including both E-field and plasmonic thermal effects revealed different enhancement factors at different excitation wavelengths and powers, in agreement with the experiment. We conclude that the performance of the MoS2 layer is enhanced by plasmon resonance energy transfer in the spectral range with strong plexcitionic resonance coupling, at longer wavelengths, whereas it is promoted by a thermal effect due to Au interband transitions at shorter wavelengths (<600 nm).

The room temperature manipulation of solid-state spins provides an opportunity to develop quantum applications under ambient conditions. Local electromagnetic fields, that usually produced by current in micro/nanoscale metal wires, have been employed for the coherent driving and addressing of spin qubit. However, the fixed distribution limits the spatial selectivity and efficiency of qubit manipulation, which is of central importance in a scaled-up quantum system. Here, we report a solution by demonstrating a reconfigurable current with arbitrary shape to engineer microwave and DC magnetic field at microscale. A "photothermal doping" method was proposed to optically control local insulator-to-metal transition in vanadium dioxide. It generates a conducting filament with adjustable position, direction, and width. Universal manipulation and selective addressing of spins at arbitrary sites are realized, by freely changing the filament and electromagnetic field on demand. Our work paves the way for developing quantum devices with large-scale spin qubits.

Silicon has emerged as a highly promising contender to replace graphite anodes in the next generation of lithiumion batteries, primarily owing to its exceptional specific capacity. Nevertheless, due to its huge volume expansion and the continuous generation of a solid electrolyte interface layer during lithiation, silicon-based anodes are difficult to apply directly in all-solid-state lithium-ion batteries. In this work, a triple strategy including a doublelayer carbon wrapping, a chemical pre-lithiation method and an in-situ polymerization technology is used jointly to design the all-solid-state Li-ion battery with high stability and excellent coulombic efficiency. The Si@C@C composites are obtained by embedded Si nanoparticles in citric acid and ZIF-8 derived bilayer carbon. Finite element simulation proves that the stress concentration caused by the lithiation of silicon has been significantly alleviated by the double-layer carbon strategy. Moreover, a chemical pre-lithiation method is introduced to compensate the irreversible loss of Li ions of the Si@C@C electrode in the first cycle, and as a result enables an increased first efficiency. Finally, an in-situ polymerization technology is developed to achieve the all-solid-state battery, in which the PDOL-SN polymerization system utilizing LiPF6 as the initiator and SN as a key additive features exceptional ionic conductivity and high oxidation potential. The as-assembled NCM811|PDOL-SN| Si@C@C-10 % all-solid-state battery shows high ICE (79.5 %) and excellent cycling stability (capacity retention: 82.4 % after 300 cycles). The methodology may be useful in designing the silicon-based all-solid-state lithium-ion battery with the purpose to address those bottleneck issues brought by the silicon negative electrode for its practical application.

Inverted perovskite solar cells (IPSCs) are among the most promising candidates for scalable photovoltaics, yet their buried interfaces remain a critical bottleneck that limits efficiency and long-term stability. In particular, the widespread use of aluminium oxide (Al2O3) nanoparticles as porous insulator contacts is hampered by severe aggregation, which obstructs charge transport and undermines perovskite crystallisation. Here, we establish a molecularly guided buried-interface engineering strategy by introducing 2-aminothiazole hydrochloride (2-ATCl) to stabilise and functionalize Al2O3 nanoparticles. This multifunctional molecule simultaneously prevents nanoparticle aggregation, enhances the hydrophilicity of self-assembled monolayers, releases lattice strain, and chemically passivates interfacial defects. The resulting devices deliver a power conversion efficiency (PCE) of 26.63% (certified 26.42%), alongside exceptional durability, retaining 90% of the initial performance after 2000 h of storage and 80% after 1000 h of continuous operation without encapsulation. Beyond conventional single-junction cells, this strategy also boosts the performance of wide-bandgap devices and proves compatible with diverse hole-selective monolayers, demonstrating its versatility. Our results present a generalizable molecular design principle for buried interfaces, paving the way towards efficient and durable perovskite photovoltaics.

Both spin textures and multiple valleys in the momentum space have attracted great attention due to their versatile applications in spintronics and valleytronics. It is highly desirable to realize multiple types of spin textures in a single material and further couple the spin textures to the valley degree of freedom. Here, we study the electronic properties of the SnP2Se6 monolayer by first-principles calculations. The monolayer exhibits rare Weyl-type and Ising-type spin textures at different valleys, which can be conveniently selected through electron and hole doping, respectively. Besides valley-contrasting spin textures, Berry-curvature-driven anomalous Hall currents and optical selectivity are found to be valley dependent as well. These valley-related properties also have generalizations to few-layer SnP2Se6 and other MP2X6. Our findings open avenues for exploring appealing interplay between spin textures and multiple valleys and designing advanced device paradigms based on spin and valley degrees of freedom.

The near-infrared (NIR) photodetector is an important component in the realm of photodetectors. Bi2O2Se, with its narrow bandgap of 0.8 eV, has emerged as a promising candidate for NIR detection. However, it exhibits a slower response in this spectral region. An asymmetric electrode structure can effectively separate photogenerated electron–hole pairs by introducing an internal electric field, thereby facilitating faster carrier transport and significantly reducing the response time. In this study, we utilized PdSe2, a semi-metal, as an electrode to construct an asymmetric electrode structure in conjunction with Ti–Au electrode, aiming to enhance the performance of Bi2O2Se NIR photodetectors. The response time of the PdSe2/Bi2O2Se/Ti–Au photodetector was 21 and 16 μs under 1064 and 1550 nm light sources, respectively, with a responsivity of 121 mA/W at 1064 nm. These findings underscore the potential of this design in advancing infrared detection technology.

Thermal-type uncooled infrared detectors, or the so-called micro-bolometers, typically based on VOx compound, have been developed and commercialized for many years. The unsatisfied temperature coefficient of resistance (TCR) of VOx and the lack of mechanical flexibility seriously limits the device sensitivity and application scenarios. Here, a flexible free-standing B-VO2/polymer film with enhanced TCR value and high absorptivity is prepared, and then a broadband infrared detector with detectivity up to 2.11 x 108 Jones has been fabricated, covering the wavelength from visible to mid-infrared region. In addition, the obtained device shows stable infrared detection performance during the bending tests, demonstrating excellent flexibility. The current studies not only provide a facile route to prepare the B-VO2-based infrared-sensitive film with high TCR values, but also achieve flexible infrared detector fabrication, which should be promising for wearable sensors and integrated infrared imaging systems in the future.

Smart windows that dynamically regulate solar spectrum transmission to reduce energy consumption in heating, ventilation, and air conditioning systems are highly desirable. However, the limited amplitude of the regulation and narrow wavelength control often degrade the modulation performance of existing smart windows. To improve solar modulation and thermal management, here we propose a three-state thermochromic smart window (TSSW) capable of modulation across the entire solar spectrum. The TSSW is mainly based on the unique phase transition properties of tungsten-doped vanadium dioxide (W-VO₂) and perovskite films, which can stepwise control the visible light and near-infrared (NIR) transmittance separately, leading to the adaptive transitions between cold, warm, and hot states. Results indicate that the TSSW achieves a solar modulation rate of 23.5%, with indoor solar irradiance decreasing from 413.6 W/m2 in the cold state to 374.5 W/m2 in the warm state, and down to 189.1 W/m2 in the hot state. The simulation results show that the annual total energy demand can be reduced by up to 102.09 WJ/m2 in some typical regions. Compared to Low-E glass and ordinary glass, this TSSW offers superior energy-saving potential, making it an ideal solution for reducing building energy consumption.

Interfacial second harmonic generation (SHG) switching mediated by insulator–metal phase transition of VO2 can serve as switchable and ultracompact nonlinear optical elements for on-chip logical optical operations. We propose that enhanced conversion efficiency and switching ratio of interfacial SHG in telecom band can be achieved with multilayer InSe/VO2 heterostructure, which has been comprehensively validated by a theoretical model of interfacial SHG and SHG spectra measurements. Our results provide solid guidance for designing interfacial SHG switching devices of high performance.

Yellow-green emitters have emerged in full-color displays, solid-state lighting, and biosensors. Currently, the solid-state yellow-green emitting materials are typically obtained through rare-earth phosphors or AlGaInN semiconductors. However, they possess an inherent radiative transition, which presents challenges in terms of color gamut and emission efficiency. Here, a centimeter-level copper-doped potassium iodide (KI/Cu) single crystal with high-efficiency yellow-green light emission was synthesized using a low-temperature water solution method. The crystal shows a broadband emission, with its center peak located at 561 nm and a large Stokes shift calculated to be approximately 200 nm. The doped copper ions introduce an isolated energy band in the electronic structure of KI, resulting in strengthened self-trapping excitons and a photoluminescence quantum yield (PLQY) of 98.98%. Based on the crystal, a white light-emitting diode with a broadband spectrum was fabricated by coupling with a UV chip, which offers new insights for yellow-green light emitting devices and their applications.

Smart windows, particularly those with broadband spectrum control, are crucial for light and heat management of the windows, which plays a vital role in building energy saving and carbon emissions reduction. The emissivity inside and outside the window seriously affects the radiation heat transfer between the room, the window and the environment, and the transparency of windows controls solar radiation heats up the room. Intelligently controlling the optical properties of windows can achieve continuous passive cooling indoors. This study proposes a smart window that synergizes the inside and outside spectral characteristics for indoor passive cooling in tropical areas. The smart window also possesses a strong emissivity of 0.9 at the outside surface and switchable emissivity from 0.20 (at high temperatures) to 0.73 (at low temperatures) at the inside surface. The window have a luminous transmission of 0.37 during the daytime but only transmit 15% of solar radiation energy. The experimental demonstration proves that the indoor air temperature can be always cooled by smart windows compared to classical low-e or common glass and 23.7% of building energy consumption can be saved in Singapore after applying the proposed smart window.

Constructing semiconductor heterostructure fiber (SHF) is a crucial strategy to advance next-generation textile-based wearable, self-powered, and long-termly comfortable optoelectronic platforms. However, in current SHF, carrier extraction/transport and stress transfer across the heterointerface usually encounter huge hindrances due to the uncontrolled structural defects (e.g., vacancies, voids, and misalignment). In this work, a molecular suturing strategy is proposed to construct meter-scale Janus WSe2/MoS2 SHF with highly aligned, densified, and electronically interconnected heterointerface by utilizing a conjugated molecular (i.e., 1,5-Naphthalenedithiol, NTD) as carrier viaduct and mechanical solder to engineer the structural defects. The obtained NTD-WSe2/MoS2 SHF exhibits over 16-fold higher responsivity (210.3 mA/W at zero bias) than previous self-powered fiber photodetectors, over 2 orders of magnitude faster photoresponse speed (38 ms) than pristine counterpart, reliable bending robustness (90.2% photocurrent retention after 60 000 bending cycles), and over threefold higher tensile strength/modulus than previous semiconductor fibers. Benefiting from these desirable performances, a robust and wearable self-powered textile photoplethysmography sensing platform is successfully developed to realize long-term (exceed 30 days) biosignal tracking. This work provides a scalable strategy for further developments of advanced wearable fiber optoelectronics.