Materials Horizons最新文献

In the context of metamaterials, decoupled access to the four constitutive parameters (permittivity, permeability, mass density, and bulk modulus) using a single architecture can unlock substantial design freedom, thereby enabling possibilities for a wide range of electromagnetic and acoustic wave manipulation applications. Herein, we propose a modular replaceable design paradigm for hybrid metamaterials to independently control electromagnetic and acoustic properties within a unified metamaterial unit cell. By arranging printed circuit board traces into an interleaved, meandering lattice, the proposed hybrid metamaterial can simultaneously generate microwave resonances for tuning of negative permittivity and permeability while acting as rigid acoustic boundaries of space-coiled air channels to produce negative mass density and bulk modulus. This hybrid metamaterial is further experimentally demonstrated to realise the simultaneous negative refraction of electromagnetic and acoustic waves. Our design paradigm represents a promising pathway toward advanced hybrid metamaterials, potentially enabling unprecedented functionalities in wave manipulation, sensing, and integrated electromagnetic-acoustic devices.

Intermetallic nanocatalysts are pivotal for advancing energy conversion and storage technologies. However, their industrial-scale synthesis is fundamentally hindered by the difficulty of maintaining precise compositional and structural control. Here, we introduce a universal phase-engineering strategy, actualized through a continuous roll-flow radiative heating platform that enables the one-step, scalable, and controllable synthesis of highly ordered intermetallic nanocatalysts. This innovative technique demonstrates remarkable versatility, rendering precise fabrication of intermetallic nanocrystals across a vast compositional landscape. Crucially, by modulating key kinetic parameters during synthesis, we achieve precise control over ordering arrangement with fine-tuning of catalytic performance. As a proof of concept, we demonstrate the scalable and sustainable synthesis of nickel-iron intermetallic (Ni₃Fe) nanocatalysts with a predominant L1₂-ordered crystal structure for efficient alkaline water splitting. The resulting catalyst exhibits exceptional electrocatalytic activity, reaching a current density of 10 mA cm^-2 at a low overpotential of 200.2 mV, a performance that rivals the commercial iridium dioxide (IrO₂) benchmark (199.2 mV). Moreover, it shows outstanding long-term durability, with 99.9% current retention over 140 hours and negligible metal leaching. A comprehensive techno-economic evaluation reveals that the hydrogen production cost is strongly dependent on current density, projecting a highly competitive H₂ price as low as $2.33 kg^-1 at 1.0 A cm^-2. This work is expected to provide advanced technology for scalable, sustainable, and continuous manufacturing of intermetallic nanocrystals for economical water splitting.

Modification of graphitic carbon nitride (g-C₃N₄) with semiconductor nanomaterials has been widely investigated as an effective method to enhance its photocatalytic activity. However, the construction of efficient g-C₃N₄-based heterojunction photocatalysts via an environmentally benign method remains critical. Herein, a two-dimensional (2D) few-layered MoS₂/S-doped g-C₃N₄ hierarchical heterojunction was successfully synthesized by a simple strategy via combining small molecule-assisted liquid exfoliation, calcination and hydrothermal strategy, which was subsequently utilized for photocatalytic formaldehyde removal. The evaluation of the photocatalytic degradation reaction showed that the as-prepared 2D/2D MoS₂/S-doped g-C₃N₄ photocatalysts exhibited superior photocatalytic activity compared to pristine g-C₃N₄ and S-doped g-C₃N₄ alone, which was attributed to the intimate interface and rapid charge transfer pathways. This heterojunction structure suppresses the excited electron-hole pair recombination within g-C₃N₄, which optimally enhances the photodegradation activity owing to high electron-hole pair separation efficiency. The few-layer MoS₂ nanosheets play an irreplaceable role due to their unique molybdenum-sulfur atomic arrangement, thereby displaying the superior electronic properties of few-layer or even monolayer nanosheets, which make them an important transfer medium for photoexcited electrons. Meanwhile, S doping effectively modulates the band gap of g-C₃N₄ and introduces sufficient structural defects to inhibit electron-hole recombination. Moreover, the synthesis employs efficient and non-hazardous reagents, and the resulting catalysts exhibit outstanding stability and recyclability for pollutant degradation.

As dynamic random-access memory continues to scale down, the feasible physical thickness of the capacitor dielectric layer continuously decreases, thus, controlling the low-k interfacial layer formed at the ZrO₂ dielectric/TiN electrode interface is becoming crucial. The interfacial layer reduces the capacitance density and increases the leakage current density, and both of them contribute to the degradation of the overall properties of the capacitor. In this study, two precursors were compared: the commonly used Cp-based Zr precursor, Cp-Zr(NMe₂)₃ [Cp-Zr] and the novel MePrCp-Zr(NMe₂)₃ [MePrCp-Zr] precursor, with the two terminal hydrogens of the Cp ligand substituted with Me and Pr groups. MePrCp-Zr was confirmed to suppress the formation of low-k interfacial layers such as TiO_x or TiO_xN_y at the initial ZrO₂ growth stage, owing to its higher reactivity than Cp-Zr. Furthermore, analysis of oxidation behavior using TiN and Ru bottom electrodes clearly revealed that the application of MePrCp-Zr led to improved interfacial sharpness compared to Cp-Zr. Electrical properties also confirmed enhanced interfacial properties, indicating that the equivalent oxide thickness decreased by 0.38 nm with the MePrCp-Zr precursor compared to Cp-Zr. This ligand-engineering strategy provides a scalable approach to achieving ultrathin high-k dielectrics with stable interfaces, enabling reliable capacitor integration for next-generation DRAM and advanced logic technologies.

Dendrimer-based nucleic acid (NA) delivery systems have attracted significant attention due to their synthetic versatility, monodispersity, nuclease resistance, high payload release, and transfection efficiency. The conventional dendrimers are non-fluorescent, limiting their utility in real-time tracking and monitoring of drug delivery. Although terminal functionalization with fluorophores can partially address this issue, it often alters critical physicochemical properties and transfection efficiency. In this study, we report the design and development of far-red fluorescent dendrimers with a naphthalene diimide (NDI)-core for efficient and traceable gene and RNA delivery. These intrinsically fluorescent dendrimers enable real-time monitoring of cellular uptake and delivery. The NDI G3 formulation effectively condenses DNA, protects it from DNase-mediated degradation, and facilitates efficient transfection in cells. Therapeutically, NDI G3 demonstrated efficient glutathione peroxidase 4 (GPX4) siRNA delivery, comparable to PAMAM G3 and Lipofectamine 3000. Notably, the NDI G3-Ca²⁺-GPX4 siRNA-FINO2 formulation sensitizes human colon cancer-derived cells to ferroptosis, synergistically annihilating cancer cells compared to treatment with FINO2 alone. The intrinsically far-red fluorescent NDI G3 dendrimer with a dynamic fluorescence response developed for the combinatorial delivery of siRNA and drug molecules offers a generalized framework for designing next-generation far-red fluorescent dendrimers for nucleic acid therapeutics and theranostic applications.

A bionic vision system integrates image sensing, memory, and computing capabilities, overcoming the limitations of traditional von Neumann architectures. However, integrating polarization-sensitivity and wavelength-selectivity while maintaining exceptional energy-efficiency, non-volatile and high-speed storage remains challenging for advanced application scenarios. Here, we present a bionic polarization vision system (BPVS) based on graphene (Gr)/CuInP₂S₆ (CIPS)/Gr/h-BN/PdSe₂ (GCGhP) ferroelectric heterostructures, which achieves polarization-sensitive and wavelength-selective vision simulation. Optical excitation-induced ferroelectric polarization reversal confines the operational wavelength to the ultraviolet band. The anisotropy of PdSe₂ introduces polarization sensitivity, while the ferroelectric polarization mechanism ensures ultra-low power consumption of 0.15 pJ/7.44 fJ (optical enhancement/electrical suppression per spike). The system mimics polarimetric synaptic plasticity and realizes memory imaging at multiple polarization angles. A bionic polarization vision neural network designed for polarization image demosaicking achieves super-resolution reconstruction. Our findings provide an effective pathway for advanced and energy-efficient polarization-sensitive bionic neuromorphic computing and vision systems.

Soft robots offer safe interactions and adaptability for underwater applications such as environmental monitoring. However, their operation in corrosive liquid environments remains a challenge due to the degradation of elastomeric components upon exposure to acids, bases, and organic solvents. Here, a universal chemical shielding strategy is introduced for elastomer-based soft robots using a spray-coated superomniphobic skin composed of fluorinated silica nanoparticles. The coating exhibits high contact angles (>150°) and low roll-off angles (<10°) for liquids spanning a wide range of surface tensions, preventing wetting and protecting against strong acids and organic solvents. The strategy is applied to representative actuators made of silicone rubber, liquid crystal elastomers, and magnetic elastomer composites, actuated by pneumatic pressure, infrared light, and magnetic fields, respectively. These coated soft robots exhibit robust swimming, crawling, shape morphing, and manipulation without degradation under harsh chemical environments consisting of toluene, sulfuric acid, and chloroform. In contrast, uncoated counterparts suffer immediate and irreversible damage. This work establishes a scalable approach to chemically resilient soft robots capable of reliable operation in corrosive liquid environments, opening new possibilities for long-term deployment in biomedicine, chemical tank inspection, polluted water remediation, and offshore infrastructure maintenance.

DNA condensate droplets (hereafter referred to as DNA condensates), which arise from specific interactions between sticky ends embedded in multi-arm DNA nanostructures, hold significant promise as programmable smart materials. However, from an engineering standpoint, the controlled preparation of DNA condensates with uniform size and a well-defined structure remains a major challenge due to the stochastic nature of the condensation process. This study presents a novel approach that employs vibration-induced local vortices (VILV) within a microfluidic platform to achieve spatial control over DNA condensate dimensions and enable their parallel generation. A key advantage of this platform is its ability to support direct observation and real-time tracking of structural morphology and dynamics. Through flow-field analysis of the VILV system, we demonstrate that uniform microvortices serve as semi-closed compartments, wherein DNA molecules confined within each vortex space rapidly aggregate and relax into uniform spherical condensate droplets. By modulating parameters such as DNA concentration and micropillar dimensions, the VILV platform not only enables systematic control of condensate size but also facilitates the construction of complex, multicomponent "patchy" condensates with consistent morphology. This platform provides a robust and scalable tool for studying liquid-liquid phase separation (LLPS) and offers broad potential for applications in the bottom-up synthesis of condensed molecular systems.

Microplastic is well known and has been the subject of many review articles. In recent years, an increasing number of reports have documented the presence of nanoplastics-plastic particles smaller than 1 µm-in various environments, from the ocean to the human brain. In this article, I focus on nanoparticles and what we do and do not understand about their effects on our health. After an introduction to nanoplastics and their size relative to a single polymer chain, the degradation process that produces nanoplastics, similar to microplastics, is briefly summarized. Due to their high surface area, nanoplastics can behave differently in solution because they tend to aggregate. After reviewing the presence of microplastics and nanoplastics in humans, insights from the established field of nanomedicine are used to explore how nanoplastics may enter the bloodstream and reach the brain. This also includes the topic of protein corona formation, which influences the fate of nanoplastics in the body. Finally, a brief summary on the impact of plastic particles on health is provided, focusing on reports comparing nano- and microplastics. This article concludes with how materials scientists and chemists can contribute to addressing the rising plastic pollution problem.

All-solid-state batteries (ASSBs) are promising next-generation energy storage systems; however, their performance is often constrained by poorly understood interfacial phenomena within composite cathode (CC) layers. In this study, we systematically elucidate how the microenvironment of CC layers, controlled by the mixing sequence of cathode active material (CAM), solid electrolyte (SE), and conductive carbon, determines the electrochemical performance of ASSBs. By preparing three representative CC configurations, we demonstrate that uniform CAM|SE interfaces promote well-developed lithium-ion transport pathways, leading to enhanced rate capability and long-term cycling stability. In contrast, poor CAM|SE contact increases charge-transfer resistance and results in premature cell failure within tens of cycles. Multiscale synchrotron-based characterizations reveal the mechanistic origin of this performance disparity. Interfacial inhomogeneity induces particle-level state-of-charge heterogeneity, which leads to localized CAM overcharging and subsequent SE decomposition. The significance of uniform CAM|SE interfaces becomes even more pronounced under practical conditions. At 30 °C, where ionic transport is intrinsically limited, ASSB cells with uniform CAM|SE interfaces maintain stable cycling performance, whereas those with less-uniform interfaces fail at an early stage. Finally, pouch-type anodeless ASSB cells operated under low stack pressure reproduce the same performance trends, further underscoring the critical role of CC microstructure control. Overall, this work establishes a direct correlation between CAM|SE interfacial uniformity, SE stability, and ASSB performance, providing practical guidelines for engineering reproducible, high-performance CC layers that bridge laboratory-scale demonstrations with real-world applications.