ABSTRACT This study explores control of the doping level in organic semiconductor films using scanning continuous wave laser radiation. The feasibility of this one‐step non‐contact post‐deposition approach is explored for a benchmark material system comprising the high‐mobility polymeric semiconductor PBTTT‐C14 p‐doped with the small‐molecular acceptor F 4 TCNQ. De‐doping is achieved via laser‐driven photothermal heating that induces neutralization and subsequent diffusion and/or sublimation of dopant molecules from the irradiated region. Comparison of 785 and 561 nm excitation, which are resonant with the absorption features of doped and neutral semiconductor, respectively, reveals that excitation at 785 nm leads to a less pronounced organic semiconductor degradation at comparable laser irradiance. Modulation of doping level is achieved with laser‐resolution‐limited feature sizes below 10 µm, with laser power adjustment enabling the tunability of electrical resistance by two and five orders of magnitude for excitation at 785 and 561 nm, respectively. This fully digital process is conducted in ambient atmosphere and does not require any additional equipment, therefore allowing straightforward integration with high‐throughput mass‐production of molecular electronics.
ABSTRACT The innovative concept of converting solid thermal conductors into flexible components is emerging as a compelling development in materials science and electronics. Flexible heatsink designs offer dynamic and adaptable solutions in the field of thermal management. This study focused on precisely fabricating and analyzing a soft and flexible heatsink, specifically designed for easy integration into foldable electronic devices, using 3D printed mold casting method. Heatsinks were fabricated using varying ratios of multi‐walled carbon nanotubes (MWCNTs) and polydimethylsiloxane (PDMS), and the preferable ratio was determined based on design factors. As a result, the functionality of a flexible heat sink was experimentally verified its potential for smart system integration. It withstood a temperature of 100°C and performed heat transfer and successfully completed repeated and continuous operation tests including 1500 bending cycles and stretching tests. The heatsink with additive MWCNTs in PDMS exhibited enhanced heat dissipation. The functionality of the flexible heatsink was experimentally presented, demonstrating its applicability in wearable devices and its potential for integration into smart systems. These results suggest that facile fabrication of flexible heatsinks can be appropriate candidates as thermal interfaces for thermal management in wearable devices and flexible applications.
ABSTRACT Androgenetic alopecia (AGA) is highly prevalent, yet its treatment is limited by systemic side effects and poor patient compliance. This study aims to develop a topical delivery system for synergistic, effective, safe, and highly compliant AGA treatment. A methacrylated hyaluronic acid (HAMA)‐based hydrogel microneedle patch (C‐F‐HMN) co‐loaded with a carbon monoxide‐releasing molecule (CORM‐401) and finasteride (FIN) was prepared. CORM‐401 and FIN were formulated into CORM‐401@Pluronic F127 (CO@F127) micelles and FIN@hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD) inclusion complexes, respectively. Efficacy, mechanisms, and biocompatibility were evaluated in a testosterone‐induced AGA mouse model. C‐F‐HMN achieved efficient local drug delivery, minimized systemic exposure, and sustained efficacy. FIN reduced dihydrotestosterone (DHT) production by inhibiting 5α‐reductase; CORM‐401 consumed scalp reactive oxygen species (ROS) and released carbon monoxide (CO) to improve the hair follicle microenvironment. Compared with monotherapy and minoxidil, C‐F‐HMN showed superior hair regrowth, activated the Wnt/β‐catenin pathway, inhibited the transforming growth factor‐β (TGF‐β)/bone morphogenetic protein (BMP) pathway, and exhibited good biocompatibility without systemic toxicity. This study establishes a novel, effective, safe, and highly patient‐compliant topical combination therapy for AGA, overcoming the limitations of traditional treatments and providing a new strategy for clinical AGA management.
ABSTRACT Dielectric materials pose a key constraint for the fabrication of complex and high‐performance printed electronics, with low‐loss dielectrics particularly important for high‐frequency applications. Here, aerosol jet printing of a benzocyclobutene‐based resin is demonstrated to support low dielectric loss, high thermal stability, stable and versatile print capability, and robust process and operational compatibility with printed conductors. This suite of characteristics is enabled by tailored ink formulation for rheological and drying properties, in‐line drying controls during printing to mitigate overspray, and refined post‐processing and characterization methodologies. Together, this enables stable printing over a wide process parameter window to achieve line width as low as 30 µm, minimal overspray, and effective leveling for smooth and dense films. The printed dielectric exhibits a degradation temperature >400°C, supporting integration with printed conductors for multilayer structures featuring excellent thermal stability even under extended thermal cycling. Moreover, dielectric characterization at 32–40 GHz using a resonant measurement configuration reveals a complex relative permittivity of 2.53–j0.004, corresponding to a low loss tangent of ∼0.002. This suite of dielectric, thermal, chemical, and process characteristics supports a compelling candidate for advanced manufacturing in microelectronics packaging, wireless communication, and sensing.
ABSTRACT Perovskite optoelectronic devices, including perovskite solar cells (PeSCs), perovskite light‐emitting diodes (PeLEDs), and perovskite photodetectors (PePDs), have attracted widespread attention owing to their tunable bandgap, high charge mobility, and ease of fabrication. With continuous efforts in performance optimization, these single‐function devices have reached a relatively mature stage. In recent years, increasing attention has been paid to multi‐modal perovskite optoelectronic devices that integrate multiple functionalities within a single device, which reduces system complexity and material consumption. In this review, the recent advances in multi‐modal perovskite optoelectronic devices are summarized. First, the fundamental principles and key characteristics of PeSCs, PeLEDs, and PePDs are introduced, and the potential for integrating multiple functionalities within a single perovskite device is analyzed. Subsequently, the optimization strategies are discussed from the perspectives of perovskite layer optimization, charge transport layer modulation, and device structural design. Finally, the current challenges and future perspectives are assessed. This work is expected to provide insights that could inspire new possibilities for multi‐modal perovskite optoelectronic devices.
ABSTRACT Cardiovascular disease (CVD) continues to be a significant contributor to premature mortality and the financial burden of healthcare. Human induced pluripotent stem cell‐derived cardiomyocytes (hiPSC‐CMs) are increasingly utilized to investigate patient‐specific genetic factors and to explore potential therapeutic options. However, contemporary technologies have yet to meet the demand for high‐throughput, real‐time assessment of physiological activity in single hiPSC‐CMs within controlled microenvironments. Here, we present a microfluidic–optogenetic hybrid platform that facilitates the systematic classification of hiPSC‐CMs according to their functional phenotypes. The optimal microfluidic droplet‐plates have been demonstrated to support the viability, morphology, and physiological function of single hiPSC‐CMs. The integration of optogenetic stimulation and optical readout facilitates non‐invasive, time‐resolved monitoring of cellular electrophysiology within each cell‐containing droplet. Our platform uniquely enables single hiPSC‐CM functional recovery and real‐time electrophysiological profiling within a microfluidic droplet‐based microenvironment. This platform offers a scalable and highly adaptable solution for phenotypic screening, disease modeling, and early‐phase drug evaluation in cardiac research.
ABSTRACT Nano‐sized hydrogel drug carriers with tailored hydro‐ and lipophilicity are designed and their encapsulation and structure‐forming capabilities investigated in real‐time. These nano‐carriers are built from cellulose and peptide hydrogels in tandem with a nano‐stacked interwoven design and alternating hydro‐ and lipophilicity, thus enabling tuning of the lipophilicity of the carrier mesh for drugs of complementary lipophilicities. This allows for a variety of therapeutic applications, based on the nanoproperties of the hydrogel. Time‐resolved and in situ grazing incidence x‐ray scattering studies confirm the design and hydro‐ and lipophilicities of the fiber‐hydrogel composite and conclude their ability for carrying drugs of complementary properties site specific. This approach allows for a novel way of understanding the functionality of drug carriers using photon‐based approach.
ABSTRACT Polymer nanocomposites offer opportunities for engineering soft materials that combine mechanical robustness with multifunctionality. However, their additive manufacturing remains challenging because high nanoparticle loading simultaneously increases viscosity and optical opacity, making these materials incompatible with conventional vat photopolymerization. Existing hybrid direct‐ink‐writing/digital‐light‐processing (DIW–DLP) systems typically process different materials independently rather than photopatterning the same composite ink deposited by extrusion. Here, we introduce a hybrid DIW–DLP (HDD) strategy based on the hypothesis that sufficiently thin layers of opaque polymer nanocomposites can still undergo rapid photocuring. In HDD, extrusion deposits thin layers of composite ink, while projected UV light independently defines geometry and lateral resolution, decoupling material deposition from shape control. This strategy enables sub‐nozzle‐gauge photopatterning and allows the uncured ink to function as a removable, self‐supporting scaffold for embedded structures inaccessible to conventional DIW or DLP. In parallel, we develop bottlebrush polymer–cellulose nanocrystal (CNC) composite inks with extremely high viscosity (up to 3 × 10 5 Pa·s) that, upon curing, exhibit an exceptional combination of softness and stretchability (Young's modulus ∼20–120 kPa; tensile strain >1600%). Together, this work establishes a framework for photopatterning highly viscous composite inks and introduces a new class of stretchable bottlebrush nanocomposites for fabricating mechanically robust, geometrically complex soft materials.
ABSTRACT Wearable health monitoring technology places high demands on flexible sensors in terms of high performance, high comfort, and multi‐functional integration. This study presents an intelligent foot perception system for wearable health monitoring. It integrates a high‐performance, flexible triboelectric sensor and a hybrid deep‐learning model. The sensor uses a MXene‐Ecoflex composite dielectric layer with a microcolumn array, which triples its output power to 0.91 mW. It demonstrates excellent linearity (R 2 > 0.99), high sensitivity (1.3 V/kPa), a wide detection range (0–200 kPa), and a low detection limit (15.6 Pa). Furthermore, we integrated the flexible sensor with a three‐axis accelerometer on a flexible printed circuit board. This constructed a wearable perception system. The system can simultaneously acquire fused pressure and acceleration signals. The system uses a CNN‐LSTM hybrid deep learning algorithm. It achieves an accuracy of 97.6% and an F1‐score of 0.98 on various motion classification tasks. Moreover, it can effectively distinguish between healthy and disabled states. This study confirms that the proposed flexible sensing system has great potential for application. It can be used for real‐time and accurate fall warning and mobile health monitoring.
ABSTRACT Realizing flexible dual‐band camouflage fabrics is fundamentally limited by the intrinsic physical conflict between visible color matching and low IR signatures, alongside the interfacial instability of functional layers during mechanical deformation. Herein, we report a highly durable fabric featuring synergistic visible‐infrared dual‐band camouflage via bio‐inspired interfacial anchoring and a gradient mechanical architecture. A reactive TA‐APTES interlayer transforms the inert textile into a functionalized interface, facilitating robust adhesion via covalent cross‐linking. Precise dual‐band camouflage patterns are achieved by fabricating an all‐polymer heterostructure (Fabric‐PANI‐PBFDO) via high‐throughput screen printing. Within this hierarchy, the PANI layer acts as a modulus‐gradient buffer, dissipating interfacial strain energy while providing high‐fidelity visible color matching with natural vegetation. The top self‐doped PBFDO layer exhibits exceptional conductivity (>800 S cm −1 ), enabling ultralow IR emissivity (ε = 0.1–0.3). Crucially, the fabric demonstrates pronounced electrothermal decoupling: generating substantial physical heat (up to 80°C) for hypothermia prevention while suppressing apparent radiation temperature to 50°C (ΔTmax = 30°C). This voltage‐driven thermal regulation allows the fabric to provide active heating while maintaining infrared outline‐disruption capability. Demonstrating exceptional radiative and mechanical stability over 1000 folding cycles, this work provides a scalable wearable textile platform for visible‐infrared dual‐band camouflage and electrothermal‐assisted infrared signature management.
ABSTRACT Low thermal conductivity (K) materials are central to energy saving, thermal management, and extreme‐environment protection. Recent advances in aerogels, polymers, porous ceramics, composites, and architected materials have greatly expanded the design space for high‐performance thermal insulators. This review summarizes the latest progress toward the ultimate thermal insulator from the perspective of heat transport regulation, with emphasis on suppressing solid conduction, gas conduction, and thermal radiation through multiscale structural engineering. Key material systems and design strategies are highlighted, together with the structure–property relationships governing ultralow thermal conductivity. Current challenges in mechanical stability, environmental durability, scalability, and practical deployment are also discussed. This review provides a concise framework for understanding the mechanism, recent developments, and guiding the design of next‐generation thermal insulating materials.
ABSTRACT Electrochemical energy devices are increasingly expected to deliver high energy and power density while also meeting requirements for safety, mechanical compliance, geometric freedom, and tight integration with sensing and control electronics. In most commercial platforms, however, these functions remain compartmentalized as electrodes and electrolytes are engineered primarily for electrochemical performance, while thermal management, gas mitigation, and diagnostics are appended as external layers or separate circuitry. This separation constrains coupled optimization of charge, heat, and mass transport, limiting the development of truly multifunctional, form‐factor–agnostic systems. This review adopts a materials‐centric hybrid‐manufacturing perspective to evaluate how additive manufacturing (AM) can overcome these constraints. We survey AM methods relevant to energy technologies such as material extrusion, electrohydrodynamic/electrostatic printing, and coating approaches that bridge conventional slurry processing with architected three‐dimensional constructs. We then examine key material families through printability–function linkages, including polymers, ceramics, metal oxides, and composites for ion transport, thermal regulation, solid‐state protection, and embedded sensing. Finally, distill microstructural design principles connecting voxel‐scale architectures to transport, percolation/tunneling networks, tortuosity and connectivity control, stimuli‐responsive pathways, and multimaterial/gradient interfaces—highlight case studies and remaining challenges in precision, compatibility, and scale‐up.
ABSTRACT We report a scalable fabrication strategy combining photolithographic patterning with chemical bath deposition (CBD) to produce ordered ZnO nanowire arrays on flexible polyimides for room‐temperature hydrogen sensing. Lithographically defined regions enable spatially controlled nanowire growth, while a tungsten‐based metallic glass buffer layer improves adhesion and mechanical stability of the sensing architecture. Systematic investigation of CBD conditions reveals that growth duration and solution chemistry strongly influence nanowire defect density and electronic transport behavior. Real‐time pH monitoring during growth provides insight into defect formation, where higher pH conditions promote defect‐rich surfaces exhibiting p‐type‐like sensing behavior, whereas extended growth at lower pH yields stable n‐type conductivity. Advanced TEM structural and spectroscopic analyses confirm the presence of oxygen vacancy‐rich surface layers (∼2–5 nm) that dominate surface charge transfer during gas adsorption. The optimized flexible sensor exhibits excellent room‐temperature hydrogen detection with responses of 241% at 500 ppm and 112.9% at 1 ppm H 2 , along with preferential H 2 response over the tested interfering gases under room‐temperature conditions, and stable operation under repeated bending. These findings establish a direct correlation between growth chemistry, defect structure, and sensing behavior in ZnO nanowire arrays and provide a scalable approach for integrating defect‐engineered oxide nanostructures into flexible gas sensors.
ABSTRACT The eutectic gallium‐indium alloy (eGaIn) is introduced as a potential non‐toxic, sustainable replacement in Mercury Intrusion Porosimetry (MIP). Contrary to the widespread misconception that gallium alloys are unsuitable for this technique due to their wetting behavior, this study shows that porosimetry measurements with non‐oxidized eGaIn are comparable to those obtained with mercury. A newly developed “eGaIn Filling Station” enables oxygen‐free preparation of standard penetrometers, facilitating high‐pressure analysis using commercially available porosimeters. Five certified and two non‐certified reference materials were analyzed with mercury and eGaIn, revealing nearly identical pore‐size distributions and total intruded volumes. Within the investigated pore‐size range, the findings show that non‐oxidized eGaIn faithfully reproduces key mercury‐based intrusion metrics while eliminating its toxicity and environmental hazards. This work provides the first demonstration of a practical alternative to mercury for MIP, offering a safe and sustainable route to preserve this essential characterization technique in compliance with global mercury regulations.
ABSTRACT Flattened amplified spontaneous emission sources are critical for high‐precision optical metrology due to their broadband, stable, and spectrally flat output. However, such sources have remained predominantly fiber‐based. Here, an integrated chip‐scale photonic module based on an erbium‐doped thin‐film lithium niobate (Er: TFLN) platform is demonstrated, achieving stable and spectrally flat broadband emission. Unlike previous chip‐scale ASE demonstrations that suffered from poor spectral uniformity or lacked practical packaging, the present module integrates a custom‐designed linearly chirped fiber Bragg grating with a fiber array packaging technology. The device exhibits spectral flatness below 2.97 dB over a 30 nm wavelength range (1540–1570 nm) and exceptional stability, with power variation less than 50 nW over 50 min. The packaged module measures only 10 mm × 2.2 mm in chip size and is fully fiber‐coupled, enabling direct integration into miniature precision systems. This work represents a crucial step toward miniaturized, robust broadband sources for demanding applications such as aerospace navigation, portable sensing, and optical coherence tomography.
ABSTRACT Constructing light‐trapping structures on the surface of perovskite solar cells (PSCs) is an effective strategy to enhance power conversion efficiency (PCE). In this study, we report a scalable microlens array (MLA) as an efficient light‐trapping structure. Four high‐refractive‐index photoresists ( n = 1.60–1.71) are prepared by doping Zirconium oxide nanoparticles (ZrO 2 NPs) into low‐refractive‐index photoresist; subsequently, we fabricate tunable refractive index MLAs with superior morphology and excellent optical performance via optimization of the photolithography process. The optical pathways in PSCs with different light‐trapping structures are investigated by means of Monte Carlo ray‐tracing simulations, and the relationship between the refractive index of MLAs and light manipulation as well as absorption enhancement is systematically analyzed based on these simulation results. In n ‐ i ‐ p perovskite solar cells, the optimized MLAs with a fill density of 22.67% and a refractive index of 1.61 boosts PCE from 25.04% to 26.16%, corresponding to a 4.47% enhancement, primarily attributed to the notable increase in short‐circuit current density ( J SC ). Furthermore, this light‐trapping structure achieves an efficiency enhancement of 8.22% in the indoor perovskite solar module. In this study, novel materials and strategies are proposed for developing highly efficient, large‐area compatible light‐trapping structures, providing a universal approach to enhance PCE of PSCs.
ABSTRACT Wrinkled surfaces, characterized by strictly periodic microstructures, can serve as templates to provide localized, repetitive microdeformations and open routes to controlled deformation properties important for strain engineering. Low‐pressure plasma treatment with various process gases tunes the localized curvature conditions of the microstructures, resulting in adjusted bending radii ranging from 20 to 3200 nm. A key challenge in achieving appropriate bending conditions is predicting the required process conditions. We demonstrate that machine learning techniques solve this prediction problem and allow precise bending adjustments. Therefore, we designed an artificial neural network (ANN) that directly maps the process parameters to the resulting wavelength ( λ ) and amplitude ( A ). By coupling this model with a bisection method, we solved the inverse design problem, allowing the derivation of possible combinations of process parameters to achieve a specific λ or A . This transforms the fabrication process from trial‐and‐error to a precisely controlled engineering workflow. Thus, our finding opens new perspectives for the tailored fabrication of wrinkled surfaces with repetitive, controlled bending in manifold applications, such as strain engineering of 2D‐materials for optical and catalytically active surfaces, or structure‐dependent localized charge accumulation, e.g., for enhanced performance of triboelectric‐based sensors.
ABSTRACT Gate‐voltage control of the superconducting critical current ( I c ) is expected to play a central role in superconducting electronics and quantum circuits, yet the underlying modulation mechanism remains unclear and reported V g values vary widely with the fabrication process. Using superconducting W–C nanowires grown by focused ion beam induced deposition (FIBID), we investigate how fabrication affects I c modulation. A three‐step focused ion beam (FIB)‐based process—(1) electron beam lithography with lift‐off, (2) He + or Ga + FIBID nanowire growth, and (3) Ga + FIB etching for cleaning—was compared with a reference process lacking the final step. We measured transport and inter‐gate leakage in devices with varied gate and nanowire widths and different ion species. Three‐step devices required larger V g, offset than the reference device, while the analysis in terms of a nominal inter‐gate electric‐field scale and dissipated gate power indicates that fabrication‐dependent leakage pathways govern the apparent voltage scale. The observed µW‐level dissipation is consistent with leakage‐induced, phonon‐mediated suppression of superconductivity, while V g, offset variations reflect fabrication residues and FIBID‐induced substrate damage. These results show that I c suppression in W–C nanowires is fabrication‐dependent and highlight controlled FIB processing combined with systematic transport measurements as an effective route to disentangle competing mechanisms in superconducting device design.
ABSTRACT The field of 4D‐printed hydrogels is largely dominated by heat‐induced contracting systems, while thermally expanding materials remain rare and challenging to implement in high‐resolution architectures. UCST‐based hydrogels could fill this gap, yet their use requires simultaneously preserving the interactions responsible for the transition and ensuring sufficient network robustness for 3D processing. As a result, UCST‐driven shape morphing has never been demonstrated in fully DLP‐printed hydrogels. Here, we introduce a minimalist system based on poly(acrylic acid‐ co ‐acrylamide) that satisfies these constraints and enables reversible and predictable UCST‐based shape transformation. Through a rational exploration of monomer concentration, crosslink density, and composition, we identify the structural requirements necessary for maintaining high thermal response. This understanding provides a formulation window for achieving 4D morphing. A first approach relies on printing objects with macroporosity to accelerate swelling in selected regions, generating transient volume differences that drive anisotropic shape changes within a single material. In parallel, multimaterial printing through vat‐switching enables the precise placement of UCST‐responsive and inert domains, making simple geometries exhibit localized deformation. In more complex structures, these selectively responsive regions can generate movements without altering their overall shape. This work opens a clear pathway to implement UCST‐based responses in 4D printed soft materials.
ABSTRACT Among the various nanoparticle synthesis techniques to address the growing demand for nanoparticles, pulsed laser fragmentation in liquids (PLFL) stands out as a simple, versatile, and sustainable method for obtaining nanoparticles (NPs) with unprecedented purity. Despite the potential to tailor the size, composition, structure, and defects of NPs via laser irradiation of a free‐flowing colloid jet, upscaling PLFL is oftentimes realized by employing costly high‐power laser sources. Herein, two improved flat‐film setups are introduced and compared with the conventional PLFL setup for the synthesis of ZnO NPs, which represent a promising model material for manifold applications. Indeed, a twofold reduction of average NP size down to less than 7 nm at 60% productivity increase and constant energy input can be achieved. Moreover, the microparticle conversion efficiency increases up to 65%, while crucial upscaling criteria, such as colloid heating, are optimized to prevent NP ripening and colloid evaporation. Numerical simulations reveal that a flat liquid surface reduces nonlinear interactions and provides more consistent irradiation conditions. The results emphasize the potential of synergistic optimization of the laser and liquid parameters for upscaled PLFL as a competitive technique for obtaining ligand‐free, green, and ultra‐small NPs.
