Miniature air movers in confined passages can exhibit rectification failure, where net throughput stalls or reverses despite sustained actuator oscillation. Here, we present a microjet air cooler with a piezoelectrically driven vibrating cantilever coupled with chamber pumping to generate tip vortex momentum carryover for sustaining airflow. We created a two-parameter stability map using the stroke Reynolds number and compression parameter, which separates pumping-secured and vortex-secured regimes from a rectification instability band. Guided by this map, we designed a laminated stainless steel shim stack prototype that generates a directed microjet with a free flow rate of 1.6 L min−1 and a volumetric flow rate density of 11.26 L min−1 cm−3. In a hotspot test, the microjet cooled a 3 W ceramic heater placed 10 mm from the outlet, reducing surface temperature from 107.5°C to 68.3°C within 120 s.
Conventional electronic tactile sensing systems mostly adopt matrix scanning and coded addressing architectures, which increase circuit complexity, slow acquisition, and limit the precision and speed of sensing. In this paper, we propose an opto-electro-mechanical copackaged tactile sensing architecture based on single-contact light-emitting diodes (SC-LEDs), fiber bundle parallel transmission, and CMOS grayscale imaging, enabling addressing-free readout. The integrated self-emissive tactile sensor includes a conductive elastomer micro-pyramid structure, an SC-LED, and the copackaged structure at the optical fiber input. The fiber bundle transmits multiple optical signals from distributed tactile sensors to the CMOS array in parallel, realizing spatial correspondence between each tactile sensor and the CMOS unit. CMOS grayscale imaging realizes the identification of the spatial distribution and intensity of multi-channel tactile signals. This architecture maps three-dimensional spatial tactile signals to two-dimensional planar optical signals, providing an integrated, scalable, and real-time solution for intelligent robotic tactile sensing.
Kim and co-workers introduce a low-temperature cold-injection (Ci) strategy that leverages pseudo-emulsion-mediated assembly of halide plumbate complexes to produce uniform and defect-suppressed perovskite nanocrystals (NCs). This scalable strategy emphasizes the importance of precursor coordination chemistry and offers a practical route toward high-performance perovskite optoelectronic devices.
Photoconductive semiconductor switches offer fast optical triggering and nanosecond-scale conduction, but their power capacity is constrained by material carrier dynamics and device architecture. Here, we report a high-power 4H-SiC photoconductive semiconductor switch. The carrier lifetime is engineered to the 100-ps range via vanadium and nitrogen co-doping for kiloampere-level current transport. A vertical-axis light injection structure decouples the electric field distribution from the current conduction channel, allowing the device to withstand 44 kV in the off state and sustain a peak operating field of 88 kV/mm. An external high-reflectivity mirror eliminates detachment and breakdown failures typical of integrated metal reflective films under electrical and optical stress. Through these optimizations, the fabricated device delivers a pulsed output with a peak current of 2 kA and a rise time of 1 ns under 26 kV bias and 52 mJ laser excitation, translating to a peak power capacity of 52 MW.
Continuous and unobtrusive monitoring of respiratory and cardiovascular parameters remains a challenge for wearable healthcare, as these metrics are typically measured using bulky medical instruments. Although skin-mounted sensors have been explored, direct skin attachment often compromises comfort and long-term wearability, and continuous monitoring of blood pressure remains difficult. Here, we present an eyeglass-based system for continuous respiratory and cardiovascular monitoring using a non-adhesive, unobtrusive interface. By integrating ultrahigh-sensitivity strain sensors into the eyeglass, the system enables real-time detection of nasal and oral breathing during daily activities. The sensors allow reliable detection of subtle respiration-induced deformations of the eyeglass nose pads. This platform demonstrates the estimation of cardiovascular trends, including heart rate and systolic and diastolic blood pressure, from respiration dynamics. Proof-of-concept demonstrations confirm that these parameters can be monitored during typical activities. This work establishes an approach for unobtrusive cardiopulmonary monitoring using everyday wearable objects.
Tactile perception is crucial for safe and effective robotic grasping and manipulation of deformable, fragile objects and human-robot interactions. Vision-based tactile sensors have emerged as a promising solution to achieve human-like touch perception. Current visual tactile sensors often require large training data and high computational costs for each individual design, limiting the widespread adoptions in practical applications. Here, we report PixelTouch, a vision-based tactile sensor that provides contact-edge, high-spatiotemporal-resolution pressure mapping (0.3 mm, 74 Hz) and self-decoupled multiaxis force measurement via micrometer-accuracy marker tracking (0.4 μm) and vector analysis. The proposed method is versatile, has low computational cost, has good transformability, and can be adopted to vision-based tactile sensors via marker tracking. A wireless miniaturized PixelTouch sensor is developed and demonstrated in a robotic gripper to autonomously complete consecutive challenging chemical-experiment tasks, including handling of a rubber-head pipette, interaction with human collaborator, liquid stirring, and viscosity assessment.
In this perspective, we present a meta-analysis of authorship, editorial board membership, and publishing models across leading biomaterials journals to characterize patterns of global participation. Our analysis reveals substantial geographic concentration in both authorship and editorial representation, with scientific visibility dominated by a limited number of regions. We further identify multiple interacting factors that shape these patterns, including national investment in R&D, access to materials and infrastructure, article processing charge structures and waiver policies, linguistic norms in scientific publishing, and geopolitical dynamics. Building on these findings, we outline targeted recommendations for funding agencies, journals, and researchers aimed at reducing structural barriers to participation. Together, these analyses highlight how current publishing and research ecosystems influence who contributes to biomaterials science and underscore opportunities to broaden participation in ways that strengthen the field’s scientific scope and global relevance.
The global rise in electronic waste and environmental pollution, driven by non-biodegradable synthetic polymers, is a growing concern. Epidermal sweat sensors enable non-invasive and real-time monitoring of sweat biomarkers, offering strong potential for personalized healthcare. Wood, as a renewable and biodegradable material, is a promising substrate for sustainable sensors. However, its integration into flexible epidermal devices remains challenging and underdeveloped. Here, we present a natural-wood-based flexible epidermal sweat electronic system (termed Sweat-Woodtronics) that readily allows automated sweat sampling and renewal via a wettability-regulated wood-based microfluidic system and real-time biomarker analysis using a wood-derived graphene (woodphene) sensing array. We test the performance of Sweat-Woodtronics in human subjects under controlled conditions. We evaluate its utility for diabetes and gout monitoring in patients and healthy controls using a fasting challenge. This work thus opens a vista of possibilities for the development of sustainable epidermal sweat sensors.
All-solid-state thermoelectric coolers provide compact, vibration-free temperature control for precision systems operating at low temperatures. State-of-the-art multi-stage Bi2Te3 coolers enable practical cooling from room temperature down to ∼170 K. Recent advances indicate that extending thermoelectric cooling toward lower temperatures requires magnetic-field-assisted mechanisms operating in both longitudinal and transverse modes. This potential integration makes it essential to clarify whether Bi2Te3 materials and coolers can maintain stable performance under magnetic fields. Here, we investigate how Bi2Te3-based thermoelectric materials and devices, in both single-stage and multi-stage configurations, respond to transverse and longitudinal magnetic fields of up to 8 T across their capable cooling temperature range of 170–300 K. We reveal the immunity of Bi2Te3 materials and device performance to magnetic fields, confirming their capability as pre-coolers for cryogenic applications and indicating a solid foundation for extending of thermoelectric refrigeration.
High pattern fidelity and thickness uniformity are challenging goals in solution-based fabrication of metal oxide patterns. Approaches to achieve these characteristics often require stringent environmental control such as low relative humidity (RH), entail prolonged drying times, or introduce unwanted residues into the films. Here, we present a surfactant-mediated surface energy-directed assembly (SEDA) process that enables the fabrication of high-fidelity, coffee-ring-free metal oxide patterns under ambient humidity conditions (RH 30%–50%). The incorporation of Triton X-100 surfactant reduces the surface tension of water, preventing moisture-induced pattern shrinkage under high-RH environments and ensuring pattern fidelity. The surfactant gradient established during drying induces a Marangoni flow, which suppresses the coffee-ring effect and yields patterns with thickness uniformity.
Droplet-based electricity generators (DEGs) harvest high-entropy mechanical energy from falling water droplets for decentralized power supply systems. However, they suffer from low energy conversion efficiency due to the reliance on liquid-solid contact electrification and displacement current generation. Here, we present a resonance-enhanced total current collection (R-TC) strategy that integrates the displacement current with the conduction current generated by an electromagnetic system and activated by droplet-induced cantilever vibrations, with an energy conversion efficiency of 20.4%. The R-TC energy harvester is experimentally validated by powering liquid-crystal display (LCD) screens and light-emitting diode (LED) bulbs, advancing droplet energy harvesting for raindrop energy scavenging and self-powered sensing.
Flexible pressure sensors are pivotal for wearable healthcare, human-machine interfaces, and soft robotics, yet their practical translation is constrained by manufacturing complexity, sensitivity-range trade-offs, and limited multifunctionality. Here, we report a laser-direct-written iontronic pressure sensor that integrates pressure sensing with pressure-modulated energy-storage capability. O/N/S-co-doped laser-induced graphene electrodes were directly patterned on Kevlar textiles, while a microstructured ionic-gel dielectric featuring ridges and gradient protrusions was fabricated using laser-engraved molds. This coupled electrode-dielectric architecture enables gradual interfacial contact evolution and efficient ion redistribution under compression, thereby enhancing electric double-layer modulation while mitigating premature saturation. The sensor delivers a quasi-linear response over 0–800 kPa, with a sensitivity of 110.04 kPa−1 and R2 = 0.946. It further enables reliable monitoring of physiological signals from subtle facial expressions to large-amplitude body motions. This work offers a scalable laser-manufacturing route toward multifunctional iontronic systems for next-generation wearables.
Implantable brain-computer interfaces (iBCIs) are approaching clinical deployment and can transform care for people with speech and motor impairment by restoring their ability in communication, movement, and aspects of agency. As a means of neurological intervention, iBCIs are not ethically or clinically analogous to current clinically established procedures or devices. They combine invasive neurosurgery, continuous neural data capture, adaptive machine-learning-based decoding, software dependence, and functionality that can change over time. These features create distinctive ethical, legal, clinical, and practical challenges that conventional informed consent frameworks do not adequately address. In this review and analysis, we present a framework and checklist to help guide more consistent and comprehensive informed consent for iBCIs to strengthen respect for autonomy, align stakeholder expectations, reduce fragmentation across sites, and support ethically robust translation of iBCIs into clinical practice.
Flapping-wing robots have better agility at small scale over fixed-wing or rotary-wing robots. In order to create robotic birds that can walk, take off, perch, fly, and land autonomously, the integration of high-energy-density power modules, optimized wing and body designs, large power-to-weight ratio actuators, and low-power and lightweight sensors and processors is required.
Tellurium-selenium (Te-Se) alloys are emerging as a materials platform capable of bridging high-mobility electronics and broadband optoelectronics. Te exhibits potentially high hole mobility but suffers from large dark current and poor thermal stability, whereas Se demonstrates ambient stability yet is limited by low carrier mobility and a wide band gap. Te-Se semiconductors provide a strategy for integrating the complementary strengths of these two elements, resulting in decreased dark current, tunable band structures, enhanced structural stability, and improved carrier transport and spectral response. Advances in solution processing and low-temperature deposition methods have expanded the applicability of Te-Se alloys to electronic and optoelectronic applications, including solar cells, sensors, thin-film transistors, and, recently, neuromorphic and multifunctional devices. This review summarizes the structural, electronic, and optoelectronic properties of Te-Se alloys, discusses synthesis strategies and device demonstrations, and highlights opportunities and challenges for their integration into applications.
Developing nonvolatile memory and logic devices that operate reliably across extreme temperatures is critical for aerospace, automotive, and deep-space applications. Here, we present a dual-gate ferroelectric field-effect transistor that combines an ultrawide-band-gap β-gallium oxide channel with an optimized hafnium zirconium oxide/aluminum oxide (8/2 nm) gate stack. The interlayer reduces the interface trap density to 1.1 × 1011 cm−2eV−1 and enables a memory window of 10.6 V with stable anticlockwise hysteresis. The device maintains reliable ferroelectric switching and nonvolatile memory operation from cryogenic (98 K) to elevated (378 K) temperatures. The wide-temperature resilience arises from competing mechanisms, i.e., between thermally activated charge compensation at high temperatures and reduced electrostatic screening at cryogenic conditions. By programming the ferroelectric polarization state, a single transistor is dynamically reconfigured between AND and OR logic, establishing a platform for harsh-environment nonvolatile memory and reconfigurable logic electronics.
Bidirectional optical synaptic plasticity is essential for hardware-based neuromorphic computing because it provides functional versatility beyond unidirectional operation. However, most reported organic optoelectronic synaptic devices remain constrained by unidirectional modulation, complex hybrid configurations, and limited mechanical adaptability, hindering their integration into electronic platforms. Here, we introduce an all-soft organic bipolar optoelectronic synapse that achieves bidirectional weight modulation through spatially selective optical stimuli. The device consists of two serially connected all-soft organic photoconductors and exploits persistent photoconductivity to emulate diverse synaptic behaviors while maintaining stable, multilevel, reconfigurable states under 50% tensile strain. We demonstrate a hardware-level vector-matrix multiplication on an all-soft, optically driven synaptic array, providing direct evidence of parallel analog computation on a fully deformable platform. By combining bidirectional optical plasticity, soft mechanical integration, and hardware-level vector-matrix multiplication, this all-soft organic synaptic platform provides a route toward optically programmable neuromorphic hardware for wearable and skin-conformal AI systems.
Organoid translation into high-throughput screening is hindered by fabrication variability and analytical bottlenecks. Here, we present an integrated experimental-computational framework coupling microfluidic encapsulation with an adaptive deep-phenotyping analytical pipeline. The integrated framework generates viable (>84%) organoids while its dual-track segmentation strategy outperforms baseline foundation models. By longitudinally tracking >10,000 images, we isolated orthogonal morphological biomarkers that non-invasively predict biological maturity. Using the framework, we identified a shape-relaxation phenomenon in which tissues converge toward spherical equilibrium, correlating with transcriptomic upregulation of focal adhesion pathways. Multi-modal characterization confirmed the physiological retention of native immune and stromal niches. The integrated framework standardizes production and validates morphological metrics as reliable proxies for molecular maturity and tissue health.
Flexible pressure sensors often face challenges related to external power dependence and signal degradation. Herein, we present an oxygen self-charging battery-type pressure sensor (OBPS) inspired by biological aerobic respiration. By constructing a reversible redox system utilizing the emeraldine/leucoemeraldine base (EB/LEB) states of polyaniline (PANI), the device achieves oxygen-driven self-charging, maintaining cathode activity without external power. Density functional theory (DFT) calculations and experimental results confirm that the integration of carbon nanotubes (CNTs) enhances electron transport, oxygen adsorption, and reaction kinetics. The resulting OBPS exhibits enhanced performance, including high sensitivity (117 mV kPa−1 in the 0–5 kPa range), rapid response/recovery times (90/65 ms), and 98.9% stability over 8,000 cycles. Furthermore, its ability to reconstruct tactile patterns facilitates applications in wearable health monitoring and human-machine interfaces.
