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Optoelectronic synaptic devices integrating light‐perception and signal‐storage functions hold great potential in neuromorphic computing for visual information processing, as well as complex brain‐like learning, memorizing, and reasoning. Herein, the successful growth of MoS2 monolayer arrays assisted by gold nanorods guided precursor nucleation is demonstrated. Optical, spectral, and morphology characterizations of MoS2 prove that arrayed flakes are homogeneous monolayers, and they are further fabricated as optoelectronic devices showing featured photocurrent loops and stable optical responses. Typical synaptic behaviors of photo‐induced short‐term potentiation, long‐term potentiation, and paired pulse facilitation are recorded under different light stimulations of 450, 532, and 633 nm lasers at various excitation powers. A visual sensing system consisting of 5 × 6 pixels is constructed to simulate the light‐sensing image mapped by forgetting curves in real time. Moreover, the system presents the ability of utilizing associated images to restore vague and incomplete memories, which successfully mimics human intelligent behaviors of association memory and logical reasoning. The work emulates the brain‐like artificial intelligence using arrayed 2D semiconductors, which paves an avenue to achieve smart retina and complex brain‐like system. [ABSTRACT FROM AUTHOR]

CsPbI3 perovskite quantum dots (QDs) are promising materials for high‐efficiency and low‐cost red fluorophores in advanced display and light‐sensing applications. However, structural and spectral stabilities of CsPbI3 QDs by traditional preparation are seriously broken in water or light environment. Here, a compositional engineering strategy with an additional PbI2‐recondition process to synthesize highly‐stable CsPbBr1.2I1.8 @ SiO2 QDs is demonstrated. Time‐ and temperature‐dependent photoluminescence and Raman measurements prove that spectral stability and exciton binding energy of QDs are greatly improved within this strategy. Notably, high‐resolution structure characterizations, point‐to‐point diffraction patterns and line‐scanning of element distributions provide strong and direct evidence at atomic‐level to reveal that PbI2‐recondition can repair defects well, which helps to construct perfect lattices and homogeneous SiO2 passivation layers to prevent the surface bonding of molecules. Moreover, our red perovskite QDs are further designed to prepare various anti‐counterfeiting labels as multi‐scale complex patterns to store and protect information. The proposed recondition strategy explores a new avenue to prepare stable and high‐quality red perovskite QDs for new‐generation lighting and light‐sensing devices. [ABSTRACT FROM AUTHOR]

In order to provide a sufficient theoretical basis for the fatigue‐resistant design of the aircraft wheels, strain‐controlled low‐cycle fatigue (LCF) tests were carried out on specimens machined in the extrusion direction (ED) and transverse direction (TD) of die‐forged 2014 aluminum alloy wheels. Although the TD specimens have lower tensile strength and yield strength, the fatigue test results show that the TD specimens have superior fatigue life compared with the ED specimens at total strain amplitudes of 0.5–0.8%. This is predominantly caused by the coarse Al12(MnSi)2(FeCu) intermetallic particles close to the surface layer, which results in a relatively short crack initiation stage for the ED specimens. In contrast, TD specimens with finer and more uniform recrystallized grains exhibit more excellent resistance to fatigue crack initiation (FCI) and propagation (FCP). Moreover, the fatigue life of alloys could be accurately predicted via a Manson–Coffin–Basquin (MCB) model based on total strain. Highlights: A new die forging method was used to fabricate the aircraft wheel.Fatigue characteristics and fracture behavior of aircraft wheels were explored.The accuracy of different fatigue life prediction models was evaluated.Coarse Al12(MnSi)2(FeCu) intermetallic particles affected fatigue crack initiation. [ABSTRACT FROM AUTHOR]

Plasmonic nanostructures have been regarded as potential candidates for boosting the nonlinear up-conversion rate at the nanoscale level due to their strong near-field enhancement and inherent high design freedom. Here, we design a hybrid metasurface to realize the moderate interaction of Fano resonance and create the dual-resonant mode-matching condition to facilitate the nonlinear process of second harmonic generation (SHG). The hybrid metasurface presents dipolar and octupolar plasmonic modes near the fundamental and doubled-frequency wavelengths, respectively, further utilized to enhance the SHG of low-dimensional MoS2 semiconductors. The maximum intensity of SHG in hybrid metasurface coupled MoS2 is more than ten thousand times larger than that of other structure-units coupled MoS2. The conversion efficiency is reported to be as high as 3.27 × 10−7. This work paves the way to optimize nonlinear light–matter interactions in low-dimensional structures coupled with semiconductors. [ABSTRACT FROM AUTHOR]

Motion recognition based on vision detectors requires the synchronous encoding and processing of temporal and spatial information in wide wavebands. Here, the dual-waveband sensitive optoelectronic synapses performing as graded neurons are reported for high-accuracy motion recognition and perception. Wedge-shaped nanostructures are designed and fabricated on molybdenum disulfide (MoS 2 ) monolayers, leading to plasmon-enhanced wideband absorption across the visible to near-infrared spectral range. Due to the charge trapping and release at shallow trapping centers within the device channel, the optoelectronic graded neurons demonstrate remarkable photo-induced conductance plasticity at both 633 and 980 nm wavelengths. A dynamic vision system consisting of 20 × 20 optoelectronic neurons demonstrates remarkable capabilities in the precise detection and perception of various motions. Moreover, neural network computing systems have been built as visual motion perceptron to identify target object movement. The recognition accuracy of dual-wavelength fused images for various motion trajectories has experienced a remarkable enhancement, transcending the previous level of less than 80% to impressive values exceeding 99%., (© 2024 Wiley‐VCH GmbH.)

Exploring novel electrode composites and their unique interface physics plays a significant role in tuning electrochemical properties for boosting the performance of sodium-ion batteries (SIBs). Herein, mixed-dimensional G/NiS 2 -MoS 2 heterostructures are synthesized in a low-cost meteorological vulcanization process. The stable graphene supporting layer and nanowire heterostructure guarantee an outstanding structural stability to tolerate certain volume changes during the charge/discharge process. The rational construction of NiS 2 -MoS 2 heterostructures induces abundant interfaces and unique ion diffusion channels, which render fast electrochemical kinetics and superior reversible capacities for high-performance SIBs. Interestingly, theoretical studies reveal that the anisotropic diffusion barriers create unidirectional "high-speed" channels, which can lead to ordered and fast Na + insertion/extraction in designed heterostructures. G/NiS 2 -MoS 2 anode exhibits a high capacity of 509.6 mA h g -1 after 500 cycles and a coulombic efficiency >99% at 0.5 A g -1 , which also displays excellent cycling performance with the capacity of 383.8 mA h g -1 after the 1000 cycles at 5 A g -1 . Furthermore, full cells are constructed exhibiting a high capacity of 70 mA h g -1 at 0.1 A g -1 after 150 cycles and applied to light LEDs. This study provides a feasible strategy of constructing mixed-dimensional heterostructures for SIBs with excellent performance and a long service lifetime., (© 2022 Wiley-VCH GmbH.)

Optical performance of the lead halide perovskites with zero-dimension (0D) structure has been in a hot debate for optoelectronic applications. Here, Cs 4 PbBr 6 hexagonal micro-particles with a remarkable green emission are first fabricated via a low-temperature solution-process employed ethanol as solvent. Our results underline that the existence of bromine vacancies and the introduction of hydroxyl induce a narrowed band gap with the formation of a defect level, which contributes to the extrinsic photoluminescence (PL) properties synergistically. Thanks to the high exciton binding energy and the unique morphology with a regular geometric structure of the as-obtained micro-particles, two-photon pumped amplified spontaneous emission (ASE) and single mode lasing from an individual Cs 4 PbBr 6 particle are realized. Our results not only provide an insight into the origin of optical emission from Cs 4 PbBr 6 , but also demonstrate that the versatile Cs 4 PbBr 6 offers a new opportunity for novel nonlinear photonics applications as an up-conversion laser.