Stretchable organic electrochemical transistors (S-OECTs) are known for their high transconductance, low operating voltage, and excellent mechanical compliance. Despite advancements in molecular design and geometric engineering, achieving both high transconductance and stable performance under a large strain remains a challenge. This study demonstrates high-transconductance intrinsically stretchable vertical OECTs, fabricated via a smooth stretchable bilayer electrode and a stretchable organic semiconductor. The combination of a smooth evaporated Au layer and transfer printing of Ag NWs endows the electrode with sub-nanometer surface roughness and high conductivity under stretching, ensuring the devices with both high transconductance (∼55 mS) and stretchability (100%). Under 100% strain, the devices successfully demonstrate rich synaptic functionalities and achieve a remarkably high paired-pulse facilitation (PPF) index of 319.82%. When configured into a reservoir computing network, the system achieves 91.76% accuracy in handwritten digit recognition under 100% strain, showcasing significant potential for wearable neuromorphic electronics applications.

Existing hydrogel-based sensing platforms confront critical limitations regarding property integration, accelerated in-mass manufacturing, and signal consistency during long-term dynamic monitoring. We address this issue by establishing a novel nano-catalytic system based on graphene oxide and L -ascorbic acid in a conventional hydrogel matrix. This system i) enables rapid ( similar to several minutes), spontaneous and large-scale fabrication under the ambient environment, ii) achieves mechanical-electrical coupling, and iii) maintains sensitive and reliable signals during sensing detection. The engineered hydrogel demonstrates a well-balanced mechanical performance, characterized by good tensile strength (235.9 kPa) and ultrahigh ductility (2522 %). Meanwhile, the corresponding sensors demonstrate high strain-dependent sensitivity (maximum Gauge factor = 11.23), highly stable repeatability, and a broad electromechanical range ( similar to 2400 %). Benefiting from its excellent self-adhesion, this hydrogel-based electronic skin displays clinical-grade accuracy in continuous pulse wave and muscle contraction monitoring. We anticipate that this innovative strategy for designing multifunctional, integrated and reliable hydrogel materials provides a basis for next-generation wearable electronics. (c) 2025 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

ABSTRACT Flexible tactile sensors are rapidly evolving toward high‐resolution, multimodal sensing and large‐area integrability, but traditional manufacturing processes face inherent limitations in complex 3D structure construction, material system compatibility, and fast and efficient manufacturing. Additive manufacturing (AM) technology, with its unique advantages such as on‐demand forming, high structural freedom, and multi‐material collaborative processing, is becoming a core driving force for breakthroughs in sensing performance and integration, moving the field toward cross‐process integration and accelerated innovation. However, AM processes and applications have not yet formed a complete system, and the development and intelligentization of AM‐based flexible tactile sensors have reached a bottleneck, urgently requiring a comprehensive and systematic review to achieve breakthrough progress. Therefore, this review systematically examines the mechanisms by which different AM processes affect the material properties, structural construction, and overall performance of devices, evaluates their applicability, process advantages, and limitations in micro‐nano structure manufacturing, and summarizes their latest advancements in intelligent systems and emerging application scenarios. Finally, it provides an in‐depth outlook on the future development challenges and potential opportunities of AM‐based flexible tactile sensors.

La-based perovskite oxides with configurational entropy increasing from low to high, namely LaMnO3, La(Mn0.5Fe0.5)O3, La(Mn1/3Fe1/3Co1/3)O3, La(Mn0.25Fe0.25Co0.25Ni0.25)O3, and La(Mn0.2Fe0.2Co0.2Ni0.2Cu0.2)O3, were synthesized by a solid-state reaction method, and their phase evolution, microstructure, and infrared (IR) radiation properties were systematically investigated. X-ray diffraction and transmission electron microscopy reveal that increasing configurational entropy at the B-site induces a structural transformation from R-3c to Pm-3m and eventually back to a stabilized R-3c phase in the five-component system, accompanied by lattice distortion and suppressed elemental segregation. Room-temperature spectral emissivity measurements show that the R-3c phase exhibits superior IR emission compared to the Pm-3m phase in the 2-8 μm range. Notably, at elevated temperatures (600-900 °C), the emissivity of LMFCNCO increases with temperature, reaching 0.910 at 900 °C, while the binary oxide LaMnO3 exhibits a marked decline. X-ray photoelectron spectroscopy indicates that the high entropy design promotes mixed-valence states of B-site cations and a high concentration of oxygen vacancies, which enhance small-polaron hopping and carrier absorption at high temperatures. This work demonstrates that entropy engineering is an effective strategy for tailoring the high temperature infrared radiation performance of perovskite ceramics, offering promising candidates for thermal management and energy conversion applications.

Developing breathable and reusable ultrathin bioelectrodes is crucial for continuous electrophysiological monitoring. Thin, dry electrodes suit long-term use but lose hydrogel advantages like near-zero half-cell potential (HCP) and adhesion, critical for detecting weak physiological signals. Polymer nanomesh-reinforced breathable hydrogel electrodes offer interfacial improvement and last similar to 10 days, yet performance degrades after extended time. This study introduces a "spinning-crosslinking-soaking" (SCS) technique to produce ultrathin (similar to 6 mu m), self-standing conductive hydrogel nanomesh (CHN) electrodes with sweat-activated ionic conductivity and adhesion, enabling dynamic, long-term reuse. The versatility of the SCS technique was demonstrated by fabricating three types of biocompatible CHN electrodes, all exhibiting low skin impedance, negligible HCP, gas/moisture permeability, and skin-like mechanics. Paired with a miniature flexible circuit, the system exhibits high-fidelity electrophysiological monitoring and can be sweat reactivated for over 100 days without skin irritation. This innovation offers a significant advancement in long-term breathable bioelectrodes, facilitating health monitoring and seamless human-centric interactions.

The precise control of copolymer topology in the copolymerization of ethylene with heteroatom-functionalized alkenes is of much interest and importance, but has remained a challenge to date. We herein report a rare-earth-catalyzed strategy that utilizes C-H activation of comonomers to precisely control the functionality and topology of ethylene-based copolymers. By employing polar styrene- and norbornene-based monomers bearing tunable C-H activation motifs (e.g., anisole or aniline derivatives), highly branched functionalized polyethylenes are obtained through effective intramolecular C-H/ethylene insertion during copolymerization, whereas polar propenyl and allyl anisole enable end-functionalized linear polyethylene via C-H-activated chain transfer polymerization. By contrast, the copolymerization of thioether analogues lacking C-H activity with ethylene yields strictly linear copolymers. Mechanistic and microstructural studies confirm that this approach provides unprecedented control over polymer architecture-including branching density, functional group placement, and chain ends-highlighting the unique ability of rare-earth catalysts to combine polar-monomer incorporation with topology control.

Laser-induced graphene (LIG) is a promising conductive nanomaterial for textile-integrated electronics due to its porous 3D network and facile maskless fabrication. However, transferring this fragile architecture onto fabrics without compromising breathability remains challenging. Conventional elastomer-based transfers rely on thick, impermeable matrices that severely trap sweat, inducing thermal discomfort and signal degradation. Furthermore, integrating active sensing nodes with traditional interconnects creates rigid heterogeneous junctions, causing severe motion artifacts during dynamic movements. Herein, we present a breathable and monolithically integrated LIG-on-textile platform via a water-assisted transfer using a low-viscosity, glycerol-plasticized poly(vinyl alcohol) (PVA-G) matrix. Upon simple water spraying, PVA-G establishes robust mechanical interlocking with textile microfibers. This secures the 3D LIG network while ensuring water vapor transmission rate (WVTR) of ~2000 g·m-2·day-1 that exceeds human perspiration thresholds. We introduce a monolithic "geometry-programmed" sensing architecture. By simply modulating the channel width, we can easily control the strain sensitivity of the LIG network. This straightforward approach enables the seamless integration of strain-sensitive active sensing nodes (width = 0.5mm, gauge factor ~1.337) and strain-insensitive interconnects (width = 7mm, gauge factor ~0.0557) within a single continuous film. This monolithic design eradicates rigid joints, effectively suppressing motion artifacts during selective joint motion monitoring for precise 3D avatar control. Supported by robust durability over 10,000 bending cycles and water-soluble disposability, these results establish the geometry-programmed LIG/PVA-G integration strategy as a reliable platform for interactive e-textiles under ambient conditions.

Organic semiconductors offering efficient mixed ionic-electronic charge transport are key components of organic electrochemical transistors (OECTs) needed for future bioelectronics and other technologies. However, hydrophobic semiconductors typically have limited ion mobility and are unstable in aqueous environments, restricting OECT applications. To address these issues, we report a broadly applicable strategy for high-performance OECTs by blending polymeric semiconductors with a photocrosslinkable hydrophilic ion-conducting supplement, poly(ethyleneglycol)-dimethylacrylate (PEGDMA). The result is ordered, interconnected semiconductor domains within an amorphous ion-conducting matrix, enabling rapid and reversible doping/dedoping without compromising charge transport. This approach enhances OECT performance across diverse electrolytes, semiconductors, and device architectures. Furthermore, PEGDMA enables high-resolution photopatterning of both semiconductors (<0.4 μm) and electrolytes (<2 μm), affording high-stability OECTs sustaining >10,000 cycles. This approach also enables wafer-scale array fabrication of 2,548 OECTs on 2" wafer, and miniaturized inverter, NAND, and NOR circuits. Also demonstrated are integration of these OECTs with a photosensor, creating a vision sensing array (10 × 10 pixels) that mimics visual image processing similar to the brain's perception system.

The precise control of copolymer microstructure, particularly to achieve self-healing polyolefins, remains a formidable challenge in the copolymerization of ethylene with polar monomers. This study combines experimental investigation with density functional theory (DFT) calculations to elucidate the mechanism of sequence-regulated terpolymerization of ethylene (E) with two distinct anisylpropylene (A (R) P) monomers by a scandium catalyst. The results reveal that steric matching drives quasi-alternating insertion of ethylene and A (R) P comonomer, leading to the formation of predominant E-alt-A (R) P sequences, while electronic effects govern the competitive selectivity among different A (R) P monomer pairs. When A (R) P monomer pairs possess similar electronic properties (e.g., A(Hex)P vs A(Naph)P), random-type terpolymers (E-A(Hex)P-random-E-A(Naph)P) are obtained. In contrast, when AP monomer pairs exhibit significant electronic differences (e.g., electron-donating A(Me/Hex)P and electron-withdrawing A(F/Cl)P), block-type terpolymers E-A(Me/Hex)P-block-E-A(F/Cl)P are formed. Experimentally synthesized block-type terpolymer E-A(Me)P-block-E-A(F)P demonstrates high toughness and rapid self-healing capability, with the E-A(Me)P block contributing to mechanical strength and the E-A(F)P block enabling fast repair, synergistically optimizing material performance. This work provides mechanistic insights into the relationships among steric/electronic effects, sequence structures, and material properties, thereby providing theoretical insights and synthetic strategies for the rational design of high-performance self-healing polyolefins.

Food safety surveillance for fresh produce requires analytical tools that operate directly on wet, curved plant and fruit surfaces, yet gold-standard methods and flexible surface-enhanced Raman scattering (SERS) substrates are often destructive or unsuitable for in vivo use. Here, we present a bottom-up absorptive ultrathin plasmonic tape-SERS-active functional elastomeric (SAFE) tape-that conforms to wet surfaces and absorbs/transports analytes to plasmonic hotspots for quantitative, multiplex in vivo SERS readouts without substrate inversion. SAFE tape swells within seconds and achieves detection limits of 1 nM for pesticides and 1 μM for plant hormones, while maintaining high signal uniformity, mechanical durability, and long-term stability. Predictive models accurately quantify mixtures across a broad range (1 μM to 1 mM). The tape also detects Penicillium spp. up to two days before visible symptoms and enables real-time monitoring of pesticide and preservative degradation during growth and storage, providing a low-cost, field-deployable platform for food safety monitoring.

Wearable bioelectronics are increasingly expected to support personalized, multiparametric, and closed-loop health monitoring, yet most systems rely on monolithic integration that limits task adaptability and increases hardware redundancy and environmental burden. Here, we present a reusable modular wearable platform that decouples a common digital back end from interchangeable analog front-end and sensing modules. This architecture enables on-demand reconfiguration across electrophysiological, mechanical, thermal, and electrochemical monitoring tasks without redesigning the complete system. Manufacturing-stage carbon-footprint analysis shows that selective reuse of carbon-intensive back-end electronics reduces emissions compared with monolithic integration, with greater benefits as task complexity increases. The platform captures muscle activity, heart-rate dynamics, electroencephalogram α-band features, body temperature, tactile, and glucose levels and wirelessly links physiological sensing to a stretchable chip-on-array LED display for real-time on-skin visualization and threshold-triggered alerts. This work provides a reusable, task-adaptive, and low-carbon hardware framework for scalable personalized wearable bioelectronics.

Vision-based robotic triaxial tactile sensing provides superior spatial resolution and rich multimodal data. However, employing rigid CMOS imagers suffers from limitations in mechanical flexibility and large-area scalability. Here we present a large-area ultraflexible photoelectrical impedance tomography (PIT)-based imager that achieves high-fidelity triaxial tactile sensing. The 5-μm-thick PIT imager incorporates a quantum dots/metal-oxide heterojunction layer with 16 peripheral electrodes, significantly reducing interconnects complexity (pixel-to-interconnect ratio >80). The device exhibits a photo-to-dark-current ratio exceeding 10⁴ under ultraviolet illumination, resolves spatiotemporal features as fine as 1.5 mm, and can simultaneously image up to five occluded regions. By integrating a thin light-scattering porous rubber and flexible LEDs, triaxial force decoding is achieved through Gaussian photocurrent analysis. The system achieves over a dynamic range of 80 kPa with a normal force sensitivity of 0.04 kPa⁻¹, a shear displacement resolution of 0.17 μm kPa⁻¹, and a topological recognition accuracy of 96.5%. We anticipate that this technology will enable advanced applications in industrial and humanoid robotics, medical and rehabilitation robotics, and wearable health monitoring and human-machine interaction systems.

Metal oxide-based electrolyte-gated transistors (EGTs) are attractive for low-power biosensors and neuromorphic systems, but their electrical characteristics has been constrained by a fundamental trade-off between channel downscaling and electrical double layer (EDL) capacitance, resulting in limited transconductance and metrics inferior to that of organic counterparts. Here, we report high-performance and ultraflexible indium gallium zinc oxide (IGZO) EGTs enabled by a vertical device architecture and a nanoscale channel length. We systematically examined how device geometries-including the IGZO-electrode contact area, IGZO thickness, and semiconductor-electrode interface-affect the electrical properties and EDL capacitance, thereby revealing how the vertical structure decouples the channel length from the EDL formation area. Optimized vertical EGTs (vEGTs) exhibit a transconductance of up to 22.5 mS, an on/off current ratio of ~105, ultralow operating voltages below 0.5 V, and pronounced ultraflexibility, maintaining stable performance when bent to a radius of 0.3 mm. Furthermore, vEGTs were integrated into inverter, NOR, and NAND logic circuits operating at voltages as low as 0.1 V. Finally, we demonstrate a closed-loop neuromorphic system in which the slow attenuation of the paired-pulse facilitation index enables adaptive and wireless control of a wearable display in response to a skin-interfaced sensor.

Stretchable surface-enhanced Raman scattering (SERS) substrates are pivotal for real-time chemical sensing on deformable surfaces but face challenges in maintaining sensitivity under mechanical strain. Here, we introduce a two-step electrodeposition and double-embedded transfer method to fabricate silver micro-kohlrabies (Ag MKs) on stretchable substrates. Ag microspheres are first electrodeposited on ITO/glass, followed by the growth of Ag nanodendrites at optimized voltage (1.3 V) and time (5 min), forming hierarchical micro-nano structures with abundant electromagnetic hotspots. A double-embedded transfer technique involving polyvinyl alcohol (PVA) and polydimethylsiloxane (PDMS) ensures robust integration of Ag MKs onto elastomeric substrates while preserving hotspot accessibility. The resulting substrate demonstrates high sensitivity with an enhancement factor of 107, uniformity, mechanical durability (50 stretch cycles at 50

Flexible surface-enhanced Raman scattering (SERS) sensors show promise for non-destructive, on-site fruit quality monitoring; however, current SERS substrates frequently fail to meet the extended operational stability demands of cross-seasonal agricultural storage systems. This study presents a durable, recyclable, and stretchable plasmonic film (Au@AgNWs/PDMS) for decay detection in grapefruits. By partially embedding silver nanowires (AgNWs) in PDMS and functionalizing surfaces with gold nanoparticles via galvanic replacement, the composite film achieves high sensitivity (10⁻9 M rhodamine 6G), mechanical resilience (85

Current toxic gas detection methods in industrial and environmental settings are limited by their reliance on manual monitoring and stationary sensors. Here, we present an autonomous mobile gas sensing system offering real-time monitoring and precise gas source localization without the need for human intervention. Room-temperature gas sensors based on high specific surface area indium gallium zinc oxide nanofibers (IGZO NFs) are developed, which exhibit low power consumption (∼0.5 mW), exceptional sensitivity (∼1290% ppb-1), and a low detection limit of 20 ppb for toxic NO2. When integrated into an autonomous mobile platform and supported by adaptive biologically inspired algorithms, the system exhibits a source localization efficiency of ∼1.5 m min-1, offering a remote, scalable, and efficient solution for detecting and localizing toxic gas leaks.

The development of high-performance, flexible, and self-healable optoelectronic materials is pivotal for advancing next-generation wearable technologies. In this study, we introduce nanoscale naphthyl-naphthyl microphase separation into a polyisoprene matrix, endowing olefin copolymers with exceptional mechanical properties, high flexibility, and intrinsic self-healing capabilities at room temperature without external stimuli. Notably, by employing a "polymer-constrained excimer" strategy, these copolymers exhibit remarkable photoluminescent properties, achieving an ultra-high photoluminescence quantum yield (PLQY > 98%) through the formation of naphthyl-naphthyl excimers. Experimental and theoretical analyses reveal that under the encapsulation of flexible cis-1,4-polyisoprene segments, nanoscale naphthyl aggregates form stable excimers upon UV stimulation, resulting in extraordinary fluorescence quantum efficiency. Additionally, the nanoscale aggregation of naphthyls imparts superior electret performance to these copolymers, making them ideal for opto-electro-mechanical sensors for the robotic hand and other devices.

Advancements in laser-induced graphene (LIG) technology enables the streamlined fabrication of 3D porous graphene-based humidity sensors. However, conventional LIG-based humidity sensors employing lateral-contact configurations often exhibit limited responsivity, owing to their partially exposed structures and dominant subsurface current pathways. This study presents a novel vertical-contact architecture that utilizes vertically aligned LIG nanotips for ultra-sensitive humidity detection. Single-pulse laser irradiation induces localized growth of the LIG nanotips, simultaneously forming in-situ vertical contacts with both the top and bottom graphene electrodes. This fully exposed structure provides a highly efficient sensing interface. By adjusting the air-gap height between the electrodes, the sensor operates in two distinct modes: Contact Mode, which achieves high responsivity (40%) via resistance modulation by water adsorption, and Remote Mode, which leverages field ionization to achieve exceptional responsivity (14 000%). The sensors demonstrate rapid response and recovery times (<1 s), excellent stability, and high gas selectivity. Integration into wearable face masks enables real-time respiratory monitoring, including hyperventilation and high-frequency breathing (up to 156 bpm), without signal degradation. This study presents a simple and scalable strategy for fabricating high-performance humidity sensors for next-generation wearable healthcare applications.