Jinyou Xu

High‐performance transparent optoelectronic synapses are highly desirable for neuromorphic vision sensors. Herein, a general strategy is proposed for developing high‐performance transparent synapse array through integration of unidirectional nanowires and transparent electrodes. The device is fabricated via two streamlined steps involving in‐plane aligned growth of millimeter‐long C8‐BTBT nanowires on sapphire substrate through nanogroove‐confined recrystallization, followed by shadow‐mask‐assisted ITO deposition. Replacing opaque metal electrodes with transparent ITO not only preserves optical transparency, but also introduces an oxygen‐vacancy‐mediated ion–electronic coupling mechanism at the ITO/C8‐BTBT interface. The synergistic effect of the ion‐electronic dynamics and the aligned nanowire architecture fundamentally tailors carrier relaxation dynamics, delivering a two‐orders‐of‐magnitude extension of persistent photoconductivity, two‐fold enhancement in paired‐pulse facilitation, two‐orders‐of‐magnitude reduction in energy consumption to picojoule level, and linear conductance modulation with >5000 incremental updates. Furthermore, the transparent synaptic array exhibits unit‐to‐unit uniformity and enables UV pattern recognition with visional retention exceeding 150 s. Benefiting from the highly linear conductance modulation, the device supports accurate four‐function arithmetic operations and UV‐encoded International Morse code decoding. This work demonstrates that the synergistic integration of unidirectional nanowires and interfacial ion–electronic coupling provides a versatile strategy for constructing high‐performance transparent optoelectronic synapses arrays, offering a compelling platform for neuromorphic applications.

The advancement of flexible and transparent photodetectors represents a technological frontier for wearable electronics and imperceptible monitoring networks. This study presents an ultraviolet (UV) photodetector that harmonizes flexibility, transparency, and water‐degradability within a minimalist bilayer architecture. The device is constructed by seamlessly depositing patterned indium tin oxide (ITO) on cast‐cured polyvinyl alcohol (PVA) films. The ITO serves dual roles as the UV‐sensitive medium and transparent conducting electrodes, while the PVA acts as both a flexible transparent substrates and low‐conductivity transport channel that effectively suppresses dark current. The resulting devices exhibit high optical transparency, retaining >89% transmittance, and a broad spectral response spanning 254–405 nm, covering UVA, UVB and UVC bands. They also demonstrate outstanding mechanical conformability, maintaining stability under extreme deformations (e.g., 60° bending angle, convex bending radii of 0.4 cm) and enduring over 5000 bending cycles with minimal performance degradation. Furthermore, they maintain stable operation under long‐term continuous illumination, high bias voltage (200 V), elevated temperature (150°C), and strong visible‐light interference. Last, the detector enables visible‐blind UV communication via ASCII and Morse encoding schemes. The seamless combination of minimalist design, high transparency, mechanical conformability, and controlled water disposability offers opportunities for imperceptible and sustainable optoelectronic applications.

Optoelectronic synapses integrate light detection and data‐processing in a single device, emerging as pivotal building blocks for efficient neuromorphic computing. The development of high‐performance optoelectronic synapses hinges on the discovery and engineering of advanced functional materials. This work presents a high‐performance optoelectronic synaptic transistor based on a MAPbI ₃ /TIPS‐pentacene heterostructure, where horizontally aligned MAPbI ₃ nanowires are grown via nanogroove‐confined recrystallization and conformally encapsulated by a spin‐coated TIPS‐pentacene layer. This rational design leverages full‐visible‐spectrum absorption and a type‐II heterointerface to achieve efficient charge separation and prolonged charge retention time. The resulting heterostructure device exhibits superior optoelectronic performance over single‐component TIPS devices, and emulates core synaptic functionalities, including enhanced excitatory postsynaptic currents tunable via optical spike parameters, a paired‐pulse facilitation index with over 200% enhancement across broad visible wavelengths and time intervals, and improved linear long‐term potentiation/depression with a two‐fold expanded maximum‐to‐minimum conductance ratio ( G _max / G _min ) of 19. When deployed in neuromorphic computing simulations, the heterojunction device achieves 96% accuracy in MNIST handwritten digit recognition and enables reliable decoding of International Morse code for optical communication. This work verifies that solution‐processed perovskite‐organic heterostructures provide a versatile and scalable material platform for the development of next‐generation neuromorphic systems and adaptive optoelectronic applications.

Perovskite nanowires offer exceptional optoelectronic properties, yet their large-scale integration into flexible optoelectronics faces challenges, including the inability to achieve epitaxial growth on amorphous flexible substrates and vulnerability of perovskites to degradation during postgrowth assembly. This work presents a nanogroove-guided crystallization strategy that enables in-plane aligned growth of CsPbBr₃ nanowires on bendable poly(ethylene naphthalate) (PEN) at 50 °C. By combining nanogrooved polydimethylsiloxane (PDMS) stamps and wettability-engineered PEN substrates, the method creates aligned nanochannels with vertically asymmetric wettability, guiding unidirectional nanowire growth without requiring lattice-matching or high-temperature processing. This approach facilitates transfer-free flexible device integration via in situ electrode deposition, preserving the nanowire's intrinsic optoelectronic properties. The resulting flexible photodetector combines a responsivity of up to 909.9 A W^-1, detectivity of up to 7.35 × 10¹³ Jones, response speed as fast as ∼50 μs, wide linear dynamic range of 89.5 dB, and robust mechanical stability─withstanding over 2000 bending cycles at a severe bending radius of 0.5 cm, underscoring the benefits of transfer-free flexible integration in harnessing the exceptional optoelectronic properties of perovskite nanowires. Last, their proof-of-concept application is showcased in optical image sensing and wireless image transmission. This study provides a scalable, low-temperature, and lattice-match-free pathway for integrating perovskite nanowires into high-performance flexible optoelectronics.

The integration of nanowires into flexible optoelectronics remains constrained by the incompatibility of lattice‐matching epitaxy with amorphous substrates and performance degradation from post‐growth assembly. Herein, a universal strategy is proposed for large‐scale oriented growth of nanowires on arbitrary substrates. By decoupling alignment from conventional lattice‐matching paradigms through topological guidance of amorphous nanogrooves, large‐area horizontally‐aligned metal phthalocyanine nanowires with consistent crystallographic axes are achieved on challenging substrates, including flexible Teflon cloth, printing paper, rigid glass, silicon wafer, and iron foil. In situ integrated flexible photodetectors using CuPc nanowire arrays on Teflon cloths exhibit broadband sensitivity (400–1100 nm), detectivity up to 10⁹ Jones, and millisecond response speeds. Mechanical robustness is demonstrated with stable operation under high bending stress (0.75 cm curvature radius) and over 1000 bending cycles. A 9 × 9 photodetector array showcases scalability, featuring consistent photoresponse across all pixels. A prototype optical communication system validates real‐world applicability, decoding Morse code signals at high speed (0.1 ms for dot) and translating light pulses into alphanumeric characters without latency or errors. This strategy bridges lab‐scale nanowire growth and deployable flexible optoelectronics, combining substrate‐agnostic alignment, in situ device fabrication, system‐level scalability, and bending‐stable operation to address integration challenges in nanowires‐based wearable technologies.

Recent advancements in artificial intelligence have spurred growing interest in developing innovative architectures for artificial synapses. Among these, nanowires have emerged as promising candidates for creating lightweight, flexible, and energy-efficient synapses. However, achieving in-plane aligned growth of nanowires on flexible substrates poses a substantial challenge for their integration into bendable synapses. This study introduces a room-temperature solution-phase graphoepitaxial growth technique that facilitates the in-plane aligned growth of nanowires along hydrophilic nanogrooves on flexible polyvinyl alcohol films. This scalable method obviates the need for complex vacuum systems and bypasses the constraints of traditional lattice-matching epitaxy by leveraging surface topography to guide nanowire alignment. Devices incorporating aligned tri-isopropylsilylethynyl pentacene nanowires exhibit a wavelength-sensitive photoresponse and mimic fundamental biological synaptic behaviors, including paired pulse facilitation and spike-number-dependent plasticity. Furthermore, these devices demonstrate exceptional bending stability, maintaining consistent synaptic response even after 2000 bends at a curvature radius of 0.4 cm. The approach's versatility is further highlighted by its applicability to the in-plane aligned growth of diverse organic nanowire arrays. By seamlessly integrating these aligned nanowires into devices without requiring post-growth transfer and assembly, this approach simplifies fabrication processes and improves device durability. This study underscores the transformative potential of solution-phase graphoepitaxial growth as a scalable and efficient strategy for advancing flexible and conformable nanowire-based devices and technologies.

The controlled growth of perovskite nanowires along predefined orientations offers significant advantages over traditional post-growth assembly strategies, facilitating their integration into compact functional devices. In this study, a nanogroove-confined recrystallization process is designed for the precise and scalable growth of oriented perovskite nanowires with millimeter lengths and high crystallinity. The process involves annealing a perovskite-containing solution sandwiched between a hydrophobic flat silicon wafer and a hydrophilic faceted sapphire wafer featuring parallel nanogrooves at 90 °C under ambient conditions. By customizing the electrode design, the nanowire arrays can be seamlessly integrated into monolithic photodetectors with large detection areas or into photodetector arrays with multiple microscale detector cells on their growth substrate. This in-situ integration strategy eliminates the need for complex post-growth processing steps. The photodetectors exhibit exceptional responsivity (38.4 A W^-1), detectivity (4.35×10¹³ Jones), and response times in tens of microseconds across the UV-vis-NIR spectrum. The seamless integration of the nanowire photodetectors opens avenues for practical applications, including high-contrast optical imaging and efficient data transmission through Morse code encoding, leveraging their high on-off current ratios and rapid response. This innovative approach streamlines the growth of highly oriented perovskite nanowires, facilitating their integration into compact optoelectronic devices.