ABSTRACT The exploration of marine environments demands intelligent sensing systems capable of stable operation underwater while performing real‐time visual information processing. Conventional neuromorphic devices, though promising for brain‐inspired computing, suffer from severe degradation in aqueous environments, limiting their application in underwater scenarios. Here, we develop a water‐resistant optoelectronic synapse based on a Rubrene/FA 3 Bi 2 I 9 /ZnO heterojunction, where the hydrophobic Rubrene layer effectively suppresses water infiltration, preserving the microstructure and optoelectronic performance of the lead‐free perovskite even after prolonged water immersion. The device exhibits various synaptic plasticities and can achieve controllable transitions from short‐term memory to long‐term memory by adjusting the parameters of the light pulses. Due to its excellent multi‐spectral response characteristics, we demonstrate the ability to filter redundant information and extract target features in complex light environments. Moreover, a 5 × 5 pixel array exhibits signal‑to‑noise separation, while a 256 × 144 resolution input frames integrated with a fully connected neural network achieves high‑precision classification of aquatic organism movement trajectories with 95.89% accuracy. This work provides a proof‐of‐concept technical path for the development of intelligent visual perception systems and neuromorphic computing hardware suitable for toward future complex underwater environments.
ABSTRACT High‐precision real‐time characterization of complex spatiotemporal light fields is crucial for super‐resolution imaging and high‐dimensional information processing. However, existing technologies still face challenges such as limited functionalities, restricted accuracy, and complicated measurement procedures. Here, a broadband metasurface‐based structured light analyzer is proposed and experimentally demonstrated. Leveraging a neural network‐driven inverse optimization model, the end‐to‐end inverse design of the metalens is achieved within a continuous geometric parameter space. By enabling comprehensive multi‐parameter detection within a monolithic metasurface architecture across the 450–650 nm range, this design offers an ultra‐compact form factor suitable for direct on‐chip integration with CMOS imaging sensors. Experimental results at 488, 532, and 633 nm reveal full Stokes reconstruction errors below 3%, with a polarization reconstruction accuracy comparable to that of commercial polarimeters. Furthermore, the reconstruction accuracy of the wavefront phase gradient is approximately 3%, supporting real‐time wavefront detection with an incident angle of up to 9°. Finally, the dynamic multi‐parameter capture of vector light fields featuring complex polarization and phase distributions is successfully demonstrated. This work provides an effective strategy for designing compact light‐field detection devices, holding promising potential for applications in structured light detection and joint polarization‐phase imaging.
ABSTRACT Conventional mechanoluminescent materials are typically designed to respond to direct mechanical contact such as compression, friction, or destructive fracture, which leads to irreversible damage and limits repetitive testing. Ultrasound‐induced luminescence (USL) offers a non‐contact, non‐destructive excitation method with deep tissue penetration and minimal material damage. In this work, we report the systematic investigation of LiTaO 3 :Tb 3+ as an efficient USL material. Under ultrasonic excitation, the material exhibits bright green emission centered at ∼550 nm, corresponding to the characteristic transitions of Tb 3+ ions. The USL intensity shows a linear dependence on ultrasonic power and correlates strongly with the microstrain generated in the material. Through thermoluminescence analysis and density functional theory calculations, three distinct trap levels were identified in LiTaO 3 :Tb 3+ : shallow traps (I, 0.56 eV) responsible for afterglow, and deeper traps (II, 0.97 eV; III, 1.40 eV) that govern the stable USL emission. Furthermore, we demonstrate the potential of LiTaO 3 :Tb 3+ for ultrasound sensing applications by inserting different intervening media (pork, acrylic, aluminum alloy). The USL intensity and microstrain exhibit consistent correlations with ultrasonic power, establishing a three‐way relationship that can be used to characterize different materials. This work provides new insights into the mechanism of USL and opens avenues for non‐destructive stress sensing.
ABSTRACT Traumatic brain injury (TBI) is a major cause of death and disability in children and young adults, leading to long‐term motor and cognitive dysfunction and neurodegeneration. Its pathological process is primarily driven by secondary neuroinflammation and oxidative stress. However, current clinical imaging lacks the resolution for real‐time monitoring of these early molecular events. Herein, we develop a microenvironment‐activatable NIR‐II nanoprobe (LnNPs‐IR775s‐ANG) based on a single‐wavelength ratiometric strategy for dynamic imaging of the key TBI biomarker‐hypochlorite (ClO − ). Leveraging the absorption competition‐induced emission (ACIE) effect, the probe enables self‐calibrated ClO − quantification via ratiometric fluorescence (F 1550, Ex808 /F 1550, Ex980 ), while the 980 nm signal serves as an indirect readout of BBB integrity. This integrated strategy allows simultaneous visualization of neuroinflammation and BBB disruption during TBI progression, offering a promising tool for early diagnosis, injury stratification, and therapeutic guidance.
ABSTRACT All‐inorganic lead‐free Cs 2 ZnCl 4 perovskite quantum dots (QDs) attract significant attention due to their non‐toxicity and unique optoelectronic properties. However, the yield of Cs 2 ZnCl 4 colloidal QDs synthesized via ligand‐assisted reprecipitation (LARP) remains extremely low, and their stability is poor, limiting their applications. Here, we report a post‐processing strategy that employs mesoporous nano‐SiO 2 to anchor Cs 2 ZnCl 4 QDs within its pores, creating spatial confinement that prevents Cs 2 ZnCl 4 QDs aggregation and quenching while passivating surface defects and reducing non‐radiative recombination pathways. This strategy enables the powderization of Cs 2 ZnCl 4 colloidal QDs, and the Cs 2 ZnCl 4 /SiO 2 nano‐composite particles (NCP) exhibit bright blue photoluminescence (CIE 0.15, 0.12). Compared to the Cs 2 ZnCl 4 colloidal QDs, the Cs 2 ZnCl 4 /SiO 2 NCP demonstrates a 10 times increase in PL intensity, with a high PLQY (74.28%) and an ultrafast photoluminescence lifetime (2.4 ns). Moreover, due to nano‐SiO 2 protection, the Cs 2 ZnCl 4 /SiO 2 NCP exhibits excellent ambient conditions (>6 months, 86.6%) and harsh conditions (temperature, humidity, light, etc.) stability, which is superior to that of other reported halide perovskite QDs. This strategy offers a viable approach to address the challenges of low yield, low photoluminescence efficiency, and poor stability in colloidal perovskite QDs, thereby creating opportunities for their commercial application.
