Key Takeaways & Executive Findings
- •• • The C8-BTBT single-crystal array achieves a coefficient of variation of 8% in synaptic weight modulation, a uniformity metric critical for reliable large-scale neuromorphic integration where polycrystalline films typically exhibit >20% variation due to grain boundaries. • • Operating at 1 V bias, the device maintains robust synaptic functionality, including learning and memory operations, enabling ultra-low-power consumption essential for edge vision systems and implantable bioelectronics. • • At 9.6 μW cm⁻² illumination, the optoelectronic synapse demonstrates pronounced photoresponsivity, facilitating pattern recognition with six grayscale intensities; focused-attention mode (V_GS = 1.5 V) suppresses background interference and resolves speckle patterns, while dispersed-attention mode (V_GS = 0.5 V) yields short-term plasticity. • • Polarity-dependent carrier trapping under positive/negative gate biases enables dynamic reconfiguration of photoresponse thresholds, emulating biological attention mechanisms and achieving long-term potentiation for adaptive, context-aware visual processing.
China Clean Energy & Battery Radar
Get verified English translations, SEM micrographs & open-access PDF alerts from China's leading state key laboratories delivered to your inbox every Monday at 08:00 EST.
Abstract
Organic field-effect transistor (OFET)-based optoelectronic synapses are pivotal for neuromorphic vision, yet polycrystalline/amorphous films suffer from grain-boundary carrier scattering and threshold instability, limiting spatiotemporal fidelity. This work employs large-area C8-BTBT single crystals to fabricate a low-voltage (1 V) optoelectronic synaptic array with a coefficient of variation of 8% in synaptic weight modulation. The grain-boundary-free structure mitigates interfacial defects, ensuring device-to-device uniformity. The array emulates human visual processing under distinct cognitive states: dispersed-attention mode (V_GS = 0.5 V) yields rapid response and short-term plasticity, while focused-attention mode (V_GS = 1.5 V) enables noise suppression and long-term potentiation via polarity-dependent carrier trapping. At 9.6 μW cm⁻² illumination, the device replicates essential synaptic functions, including learning and memory. Pattern recognition tests with six grayscale intensities demonstrate that the concentration state enhances photoresponse sensitivity and contrast discrimination, resolving fine details such as speckle patterns on bird plumage, whereas the moderate attention state fails to resolve such features. This platform advances hardware-level perception-computation integration for biomimetic vision chips, offering a pathway to energy-efficient, context-aware neuromorphic systems.
1. Introduction
Conventional von Neumann architectures face fundamental limits in energy efficiency and parallelism, consuming excessive power for sensory data processing. Biological neural networks, by contrast, operate at ~10 fJ per synaptic event via 10¹⁵ synapses, seamlessly integrating memory and computation. Existing organic synaptic devices predominantly rely on polycrystalline or amorphous films, which suffer from grain-boundary-induced carrier scattering and threshold voltage instability, degrading spatiotemporal emulation fidelity and device-to-device uniformity. These defects constrain the reproducibility required for neuromorphic circuits and hinder the transition from passive sensing to active cognition in flexible electronics.
This study addresses the bottleneck by employing large-area C8-BTBT organic single crystals, which offer long-range molecular order, ultralow defect densities, and exceptional charge transport uniformity. The resulting optoelectronic synaptic array operates at 1 V with an 8% coefficient of variation in synaptic weight modulation, enabling reliable replication of synaptic dynamics. By modulating gate voltage to emulate attentional states, the system achieves dispersed-attention (rapid response, short-term plasticity) and focused-attention (noise suppression, long-term potentiation) modes, demonstrating hardware-level perception-computation integration for biomimetic vision chips.
Loading authentic research manuscript (Pages 1–5)...
HE Lihua, ZOU Yi, LI Chengtai, DUAN Shuming, REN Xiaochen, HU Wenping (2025). Vision System Utilizing Large-Area Organic Single Crystals for Sensory Applications. SCIENCE CHINA Materials. https://doi.org/10.1007/s40843-025-3641-y
Research & Educational Purpose Only: The translations, structured abstracts, analytical annotations, and data reports provided by SinoGreenTechare intended exclusively for academic research, internal corporate R&D, and educational benchmarking. They do not constitute formal engineering, chemical safety, legal, or professional advice.
Copyright & Intellectual Property Notice: Original copyright of the underlying source articles and experimental data remains with the respective authors, institutions, and original publishing journals. SinoGreenTech claims intellectual property only over its proprietary translations, analytical syntheses, and AEO structured enhancements in accordance with international fair use and academic citation principles.
Frequently Asked Questions
What is the operational lifetime and degradation rate of the C8-BTBT single-crystal synaptic array under continuous bias stress?
The provided text does not specify degradation rates or lifetime data. However, the grain-boundary-free single-crystal structure inherently mitigates interfacial defects, which typically cause threshold voltage shifts in polycrystalline devices. The 8% coefficient of variation in synaptic weight modulation indicates high uniformity, but long-term stability under prolonged bias (>1 V) and illumination remains to be quantified in accelerated aging tests.
How does the 8% coefficient of variation compare to state-of-the-art polycrystalline OFET synaptic arrays, and what is the yield of functional devices across the large-area array?
The 8% coefficient of variation is significantly lower than typical polycrystalline arrays, which often exhibit >20% variation due to grain boundaries. The text does not provide device yield, but the large-area single-crystal growth method implies high uniformity. Industrial scalability would require >95% yield, which is not addressed in the current study.
What are the failure mechanisms under high humidity or temperature fluctuations, and how does the single-crystal device mitigate them?
The text does not discuss humidity or temperature effects. Single crystals generally offer better environmental stability than amorphous films due to lower defect densities and reduced ion migration. However, without encapsulation, organic materials remain susceptible to moisture and oxygen. The polarity-dependent carrier trapping mechanism may be influenced by temperature, but empirical data are lacking.
What is the cost parity of large-area organic single-crystal fabrication against commercial silicon-based neuromorphic chips, and what are the scalability bottlenecks?
The text does not provide cost analysis. Organic single-crystal growth methods (e.g., solution shearing) can be low-cost, but large-area uniformity and throughput remain challenges. Silicon-based chips benefit from mature infrastructure. The 1 V operation and low power consumption could offset initial costs in flexible electronics, but economic viability requires further techno-economic assessment.
How does the gate voltage modulation (0.5 V vs. 1.5 V) affect the dynamic range and linearity of synaptic weight updates, and what is the endurance cycle limit?
The text states that V_GS = 0.5 V (attention) and 1.5 V (concentration) yield distinct responsivity to six light intensities, with the concentration state showing enhanced sensitivity and discriminability. However, linearity and endurance are not quantified. The carrier trapping modulation suggests potential for multistate retention, but cycle-to-cycle variation and endurance limits require further study.
Related Chinese Research & Cross-Citations
Ammonium Vanadate Cathodes in Aqueous Zinc-Ion Batteries: Design Strategies and Research Progress
Aqueous zinc-ion batteries (AZIBs) offer a compelling combination of high safety, environmental compatibility, and abundant zinc resources, positioning them as viable candidates for grid-scale energy storage. Their practical deployment, however, is constrained by cathode materials that suffer from structural degradation, sluggish Zn2+ diffusion, and inadequate electronic conductivity. Ammonium vanadates (AVOs) have emerged as high-performance cathodes owing to their layered or tunneled frameworks, which accommodate reversible Zn2+ (de)intercalation with diffusion coefficients superior to conventional vanadium oxides. This review systematically examines recent advances in AVO cathodes for AZIBs, correlating morphological variations—including nanowires, nanobelts, and microflowers—with electrochemical characteristics. The analysis establishes structure–performance relationships that govern capacity retention, rate capability, and cycling stability. Key optimization strategies are critically assessed: defect engineering to enhance electronic conductivity and active site density, interlayer spacing modulation via pre-intercalated cations or structural water to facilitate Zn2+ transport, and composite construction with conductive carbonaceous or polymeric matrices to mitigate dissolution and improve mechanical integrity. Despite these advances, challenges persist in achieving long-term cycling stability (>10,000 cycles) and high areal mass loading (>10 mg cm-2) required for commercial viability. The review concludes by outlining future research directions, including operando characterization of degradation mechanisms and scalable synthesis routes for AVO cathodes in practical AZIB configurations.
Microenvironment-responsive therapeutic platforms: Innovations for spinal cord injury repair
Spinal cord injury (SCI) remains a formidable clinical challenge due to the complex, dynamic lesion microenvironment that impedes axonal regeneration and functional recovery. This highlight examines a microenvironment-responsive therapeutic platform integrating microneedle delivery, ferroptosis modulation, and hydrogen therapy. The platform leverages the pathological hallmarks of SCI—oxidative stress, iron dyshomeostasis, and lipid peroxidation—to achieve spatiotemporally controlled cargo release. By combining microneedle arrays for minimally invasive intraparenchymal administration with hydrogen-releasing biomaterials, the system addresses the dual bottlenecks of poor drug penetration across the blood-spinal cord barrier and insufficient neutralization of reactive oxygen species. Ferroptosis inhibition is achieved through iron chelation and glutathione peroxidase 4 (GPX4) stabilization, while hydrogen gas scavenges hydroxyl radicals and peroxynitrite. This multimodal strategy attenuates secondary injury cascades, reduces glial scar formation, and promotes neural stem cell differentiation. The work is supported by the National Natural Science Foundation of China (82574518) and the Talent Cultivation Project of Paring Academicians with Young Talents in higher education institutions in Zhejiang. The authors declare no conflict of interest. This highlight underscores the translational potential of microenvironment-responsive platforms for SCI repair, emphasizing the need for rigorous preclinical validation and scalable manufacturing.
Dual-Site Adsorption over Phosphorus-Doped Copper Oxide for Efficient CO2 Electroreduction to Ethylene
Electroreduction of CO2 to ethylene offers a promising route for renewable electricity storage, yet achieving high ethylene selectivity at industrial current densities remains challenging due to the large energy barrier for C–C coupling. Here, we report a “MOF-assisted in situ doping” strategy to introduce the oxophilic nonmetal phosphorus (P) into the copper oxide (CuO) lattice, constructing a localized Cu–P dual-site adsorption configuration for the key *OCCHO intermediate. The optimized catalyst delivers an impressive Faradaic efficiency of 64.6% for ethylene with a partial current density of 646 mA cm-2. Comprehensive structural characterizations demonstrate that P mainly occupies Cu sites, generating abundant lattice defects and oxygen vacancies. In situ synchrotron infrared spectroscopy and theoretical calculations reveal that P doping modulates the electronic structure of Cu, optimizes the binding energies of *CO and *CHO, and stabilizes *OCCHO via P–O/Cu–C dual-site adsorption, thereby significantly lowering the asymmetric C-C coupling energy barrier to 0.74 eV. This work highlights a dual-site microenvironment regulation strategy for CO2-to-ethylene electroreduction.
Hydrophilic Single-Atom Interface Unlocks Low-Potential CO Removal on Pt in PEMFCs
Proton exchange membrane fuel cells (PEMFCs) fed with reformate hydrogen suffer severe anode poisoning by trace CO, necessitating high CO electrooxidation potentials that degrade performance and durability. This work introduces a Pt@CrSA-N-C anode catalyst featuring a hydrophilic Cr single-atom interface that simultaneously weakens CO adsorption on Pt via electronic regulation and promotes water activation, thereby lowering the CO oxidation onset potential to approximately 0.13 V vs. RHE. The onset potential was determined by two independent methods: the first potential at which the background-corrected current exceeds 0 mA cm-2 during CO oxidation reaction tests in a three-electrode system, and the potential at which the forward scan current exceeds the N2 background current in CO-stripping voltammetry. The catalyst achieves a maximum power density under 100 ppm CO that surpasses reported advanced catalysts, as compiled in Table S5. Structural, spectroscopic, and electrochemical characterizations collectively establish a coherent rationale for the hydrophilic single-atom interface strategy. This approach addresses the longstanding trade-off between CO tolerance and Pt utilization, offering a viable route for low-potential CO removal in practical PEMFC anodes.
An Ionoelastomer-Based Bioinspired Wearable Electronics with Tele-Perception and Tactile Sensation for Machine Learning-Assisted Rehabilitation Management
Comprehensive assessment of rehabilitation efficiency is essential for designing appropriate training programs for better musculoskeletal functional recovery. Existing contact-receptor-dependent rehabilitation assessment systems mostly focus on assessing the restoration of muscle function by evaluating grip strength or joint flexion angle; however, parameters reflecting neuromuscular synergistic function are always overlooked. Herein, we develop an ionoelastomer-based soft artificial electroreceptor (SAER) that integrates tele-perception and tactile sensation to track the rehabilitation process, collecting signals related to approaching speed and grip strength sequentially. The SAER uses polyurethane ionoelastomer incorporated with quasi-solid conductive salt as the electric field receptor, and is integrated on a rehabilitation-training ball after assembly to establish an untethered detection device; this enables the remote capture of hand approaching parameter within a 9 cm range, followed by the quantification of grip strength when contacting and grasping. Furthermore, a data-driven assessment system is established by integrating machine learning, which accurately classifies rehabilitation efficiency into six levels; it supports for rehabilitation evaluation and training programs adjustment. Overall, the SAER-based rehabilitation management system establishes a paradigm that synergistically evaluating parameters corresponding to neuromuscular functional restoration and holds strong potential for home-based active rehabilitation for minimizing dependence on frequent clinical supervision.
Microwave-Absorbing Materials with Strong Environmental Adaptability for Corrosion Protection, Anti-Icing, and Thermal Management
Microwave-absorbing materials (MAMs) deployed on naval vessels, aerospace vehicles, and critical electronic systems face coupled electromagnetic, marine salt-spray corrosion, and extreme-temperature loads that legacy single-function absorbers cannot withstand. This review consolidates progress on three environmentally adaptive MAM classes: corrosion-protective, anti-icing, and thermal-management absorbers. The electromagnetic loss and impedance-matching fundamentals are first established, then the synergistic mechanisms, design strategies, and characterization protocols for each class are examined against representative material systems and their measured performance. The analysis identifies a shared design logic—multiscale hierarchical architecture, interfacial polarization engineering, and multifunctional phase integration—while distinguishing the divergent protection mechanisms: barrier and passivation effects for corrosion, surface-energy and latent-heat regulation for anti-icing, and phonon–electron transport decoupling for thermal management. Persistent bottlenecks include the trade-off between impedance matching and protective-layer density, the absence of standardized coupled-field test protocols, and the scarcity of long-term salt-spray and thermal-cycling durability data. Future directions are delineated: intelligent self-adaptive absorbers, multiphysics-coupled simulation frameworks, and environmentally benign multifunctional integration. The review provides a theoretical and technical basis for the design, construction, and engineering scale-up of next-generation high-performance absorbers for aerospace, electronic, and marine equipment.