ABSTRACT Artificial neurons are considered an effective approach to alleviating the challenges of large data throughput and high‐power consumption in electronic tactile sensory systems. However, emerging artificial neuron implementations beyond conventional silicon circuits are still limited in enabling low‐power operation and large‐scale scalability. Oxide semiconductors provide an energy‐efficient platform for neuromorphic circuits, owing to their low leakage current, while offering fast, gate‐controlled switching. Here, we report an Axon‐Hillock (A‐H) artificial neuron circuit based on solution‐processed indium oxide (In 2 O 3 ) transistors. The neuron circuit contains a two‐stage high‐gain (∼180 V/V) inverter composed of four In 2 O 3 transistors, a leakage transistor, and a capacitor, exhibiting >20 kHz frequency response, tunable output spike frequency up to 500 Hz, and ∼62 nW power consumption. Integrated with a pressure sensor, the neuron effectively converts tactile pressure into spike trains at the sensing interface. We further demonstrate in‐sensor spike encoding of tactile stimuli and validate texture recognition with a spiking reservoir network (SRN), achieving ∼88% test accuracy over 20 fabric classes. These results demonstrate the feasibility of implementing solution‐processed oxide materials in energy‐efficient neuromorphic electronics.

ABSTRACT Achieving both broad bandwidth and high frequency in a single sensor is challenging but essential for high‐resolution heterostructure photoacoustic diagnostic imaging. Such capabilities can provide early‐stage disease detection signatures and eliminate need for multiple sensors. While promising, we present the first fabrication and demonstration of nanofiber‐based photoacoustic sensors, enabling high‐frequency broad‐bandwidth photoacoustic (PA) signal detection due to the flexible nanofibers' network that allows the absorption of acoustic energy over large frequency range and conversion of mechanical vibrations into electrical signals efficiently. A customized electrospinning system is designed for synthesizing nanofibers on a heated substrate using composite solution of polymer PVDF‐TrFE and cubic single‐crystal nanoparticles. Synthesized nanofibers provide a large surface area, with BTO around the surface of nanofibers, resulting in higher polarization, crystallinity, and charge generation while making proper electrical contact using loaded high pressure. These composite nanofibers are characterized and optimized for sensor fabrication. Fabricated sensors are used to detect photoacoustic signals from various sources including eumelanin and hemoglobin. Photoacoustic signals of central frequencies (1.5–33.2 MHz) and bandwidth (209%) are recorded. The sensors are further used for PA imaging with a human subject and a chicken phantom, showing potential applications of the developed sensors in clinical diagnostics.

ABSTRACT Stretchable ionic conductors are attractive for wearable electronics, yet combining high strain sensitivity, fatigue‐crack resistance, and cyclic electromechanical stability in an ionic‐skin platform remains challenging. Here, we develop fatigue‐resistant kirigami ionic skins based on elastic and tough segmented polyurethane ionogels. The ionic liquid preferentially plasticizes soft segments to form continuous ion‐transport pathways, while the hard segments act as reinforcing domains that redistribute stress and suppress crack initiation and growth. The optimized ionogel reaches 2533% stretchability, 125 MJ m −3 toughness, and 42.5 kJ m −2 fracture energy, with no measurable notch growth after 10,000 cycles at 100% strain. Leveraging this robust conductor, we pattern a single conductive track with a periodically repeated V‐shaped kirigami layout and laminate it onto an elastomeric backing to enable geometric strain amplification with reversible cut opening and closure. The ionic skins reach a gauge factor of ∼65, show low hysteresis (<5%), and sustain stable response over 1000 cycles, while exhibiting weak cross‐talk to superimposed normal pressure and a response time of ∼120–140 ms. Feature extraction plus an artificial neural network (ANN) classifier enables ≈99% recognition of graded knee motions. This materials‐architecture‐data strategy offers a scalable route to fatigue‐resistant, high‐fidelity ionic skins for soft electronics and rehabilitation interfaces.

ABSTRACT In this paper, a dual‐layer metal‐only Huygens' metasurface (HMS) based on air medium is proposed to achieve independent phase and amplitude control of linearly polarized electromagnetic (EM) wave for sidelobe suppression in a transmissive metasurface configuration. The unit cell consists of two identical layers, each containing an inner concentric extended split‐ring slot (CESS) and an outer concentric split‐ring slot (CSS). Phase modulation based on Huygens' principle is realized by adjusting the physical parameters of the slots to manipulate the orthogonal electric and magnetic resonances, while amplitude is controlled by rotating the structure to modulate the co‐polarized transmission based on its polarization selectivity. To validate the design concept, a phase and amplitude modulated transmissive metasurface called TM‐II is designed and fabricated. For comparison, a base design employing phase‐only modulation called TM‐I is also realized. The measured results show that the TM‐II with amplitude tailored to follow the Taylor distribution improves the sidelobe level (SLL) by 1.6 dB in the xoz plane and 6.1 dB in the yoz plane compared to the phase‐only modulation design. This proposed HMS offers a new approach for independent phase and amplitude control, which could be applied to point‐to‐point communications, satellite systems, and high‐power applications.

ABSTRACT Continuous and long‐term pressure monitoring by devices implanted in the human body promises substantial improvements for diagnosis, health monitoring, surveillance of disease progression, or surveillance of the response to a treatment but also for precision during surgeries. Here, we report on a piezoresistive sensor made entirely of parylene‐C eliminating the need for heterogeneous encapsulation. Material characterization demonstrated that parylene‐C is excellently suited as a construction material. The pressure sensor comprises a parylene‐C membrane, which is functionalized with gold strain sensors for pressure sensitivity. It was bonded to the reference pressure cavity, thereby establishing a long‐time stable hermetic sealing. The presented design and fabrication enable for the first time a monolithic, highly soft and flexible pressure sensor entirely made of biocompatible material. It exhibited high pressure sensitivity of up to 6.2 µV·mmHg −1 with very good repeatability and negligible hysteresis, made possible by thin‐film strain sensors on a parylene‐C membrane with a gauge factor of 7.5. Simulations show how the design can be easily even further miniaturized. Initial in vitro assay confirmed that parylene‐C is biocompatible on cell culture level. Such biocompatible and chronically implantable pressure sensors are opening new possibilities in medical treatments and long‐term supervision.

ABSTRACT Magnetic nanoparticles (MNPs) are attracting increasing attention for applications in energy, environment, and biomedicine. Among all MNP synthesis methods, ball milling is a cost‐effective route for producing large quantities of MNPs at low cost. This work aims to investigate the magnetic hyperthermia performance of MNPs synthesized through a mechanochemical ball milling approach. Herein, we first varied the milling conditions and thoroughly characterized the physical properties of the produced MNPs; later, their hyperthermia performance was studied under different alternating magnetic fields (AMF). We report that the MNPs, after ball milling for up to 55 h at 200 rpm, show a higher magnetite phase with an average hydrodynamic size of ∼270 nm and irregular morphology. These MNPs were subjected to clinically safe AMF (30 mT, 101.5 kHz), yielding a maximum temperature rise of ∼50°C, including in the SKOV3 cancer cell medium. Additionally, to enable controlled heating and avoid unintended damage to healthy tissues, we applied pulsed AMFs, achieving a temperature of ∼30°C. Lastly, the cellular uptake, colloidal stability, and biocompatibility tests were conducted on suspensions. This study reports a straightforward, cost‐effective, large‐scale synthesis route for MNPs and highlights their effective hyperthermia performance, showcasing their potential for future safer tumor treatment.

ABSTRACT Ultrasound transducers made from rigid piezoceramics are difficult to adapt for wearable or conformal applications. Piezopolymer‐based transducers offer a practical alternative; however, most existing studies focus on piezoelectric materials, while the influence of electrode material and electrode–polymer interface remains underexplored. This study leverages different interface‐engineering strategies to examine the influence of electrode–piezopolymer interface morphology on piezoelectric, dielectric, and acoustic behavior in flexible transducers. Devices were fabricated using silver (Ag), gold (Au), graphene flakes (GF), laser‐induced graphene (LIG), and Au‐decorated LIG electrodes, enabling comparison across interfacial architectures. LIG‐based transducers showed strong acoustic and piezoelectric output due to partial infiltration of the piezopolymer into the porous LIG network, which enhances interfacial contact and stress transfer. Au‐based transducers achieved comparable acoustic output. In contrast, dense Ag electrodes and layered GF films provided limited coupling, resulting in reduced electromechanical response. LIG‐based transducers exhibited the highest flexibility and durability, retaining stable performance after 10,000 bending cycles and an eight‐week aging study, whereas GF, Ag, and Au devices degraded under bending, and Ag electrodes declined over time. These findings demonstrate that engineering the electrode–polymer interface is critical for high‐performance flexible ultrasound transducers and identify LIG as a strong candidate for wearable imaging applications.

ABSTRACT A 5Y‐PSZ zirconia paste was formulated for extrusion‐based additive manufacturing via Direct Ink Writing (DIW) to produce dense ceramic components for dental applications. A colloidal approach was adopted using nanometric zirconia powder (47 vol%) with tailored dispersant, thickener, and flocculant agents. Rheological behavior was evaluated by shear viscosity, viscoelastic moduli, and three‐step thixotropy tests to ensure printability and shape stability. Specimens were printed with different filament overlap percentages (20%, 25%, and 30%) and compared with a control group obtained by uniaxial pressing. After sintering, all groups were characterized in terms of relative density, microstructure (SEM), phase composition (XRD), translucency, and biaxial flexural strength. The 30% overlap printed group achieved average densification above 99%, optical translucency comparable to the pressed controls, and flexural strength of 432 ± 37 MPa. Weibull analysis of 30% filament overlap group indicated σ 0 = 420 MPa and m = 7.0, comparable to the pressed group (σ 0 = 658 MPa; m = 7.3). Overall, this study establishes a robust formulation and processing route for DIW of 5Y‐PSZ with high densification, translucency, and mechanical reliability, fulfilling ISO 6872 and offering a viable alternative for dental applications. This is the first study demonstrating filament overlaps as a densification‐enhancing parameter for DIW zirconia.

ABSTRACT This study reports biodegradable polymer coatings incorporating a naturally derived antimicrobial peptide to provide sustained infection control and enhance regenerative healing of titanium bone implants. Titanium is widely used for permanent implants due to excellent mechanical properties, and additive manufacturing enables patient‐specific, porous architectures that promote osseointegration. However, bacterial colonization and periprosthetic infection remain significant challenges, particularly for complex porous geometries. We developed a straightforward solvent‐casting method to apply polycaprolactone (PCL) coatings loaded with the host defense peptide caerin 1.9 (F3) onto additively manufactured Ti‐6Al‐4 V scaffolds with gyroid triply periodic minimal surface structures. As‐built scaffolds (≈56% porosity) exhibited substantial roughness from partially melted powder, whereas polishing increased porosity (≈66%), removed surface defects, and improved crack resistance. Peptide‐loaded PCL coatings provided sustained in vitro antibacterial activity for up to 168 h and demonstrated in vivo protection beyond 72 h in a murine model challenged with methicillin‐resistant Staphylococcus aureus . The coatings showed no cytotoxicity and promoted increased expression of proteins associated with tissue healing. These dual‐function antimicrobial and pro‐regenerative coatings offer a promising strategy to improve the safety and biocompatibility of additively manufactured titanium implants.

ABSTRACT Human skin perceives complex external stimuli through the coordinated detection of temperature, static strain, and dynamic strain. However, current skin‐like multimodal sensors are typically limited to dual‐mode sensing or suffer from signal interference and excessive wirings. In this study, a soft, skin‐like tri‐modal sensor capable of independent and simultaneous detection of temperature, static strain, and dynamic strain is reported. The sensor consists of a single, skin‐inspired sensing layer of a soft, piezoelectric and ionic composite film that is sandwiched between stretchable electrodes. It uses distinct frequency‐domain responses: charge relaxation time for temperature, normalized capacitance for static strain, and piezoelectric charge output for dynamic strain—to fully decouple signals without the need for separate sensors. Practical demonstrations include simultaneous detection of skin temperature and pulse waves at the wrist, localized mapping of strain and temperature under shear stress, and texture recognition through dynamic force sensing. This work provides a compact and scalable platform for fully decoupled tri‐modal sensing, paving the way for intelligent prosthetics, on‐skin electronics, and interactive robotics.