http://onlinelibrary.wiley.com/rss/journal/10.1002/(ISSN)1521-4095

Super-hard wood-based composites (WBC) are designed and developed inspired by the mesoscale homogeneous lignification process intrinsic to tree growth. This innovative hybrid structure is achieved by leveraging the infusion of low-molecular-weight phenol formaldehyde resin into the cell walls of thin wood slices, followed by a unique multi-layer construction and high-temperature compression.

The growing demand for high-strength, durable materials capable of enduring extreme environments presents a significant challenge, particularly in balancing performance with sustainability. Conventional materials such as alloys and ceramics are nonrenewable, expensive, and require energy-intensive production processes. Here, super-hard wood-based composites (WBC) inspired by the meso-scale homogeneous lignification process intrinsic to tree growth are designed and developed. This hybrid structure is achieved innovatively by leveraging the infusion of low-molecular-weight phenol formaldehyde resin into the cell walls of thin wood slices, followed by a unique multi-layer construction and high-temperature compression. The resulting composite exhibits remarkable properties, including a Janka hardness of 24 382 N and a Brinell hardness of 40.7 HB, along with exceptional antipiercing performance. The created super-hard, sustainable materials address the limitations of nonrenewable resources while providing enhanced protection, structural stability, and exceptional resilience. The WBC approach aligns with UN Sustainable Development Goals (SDGs) by offering extra values for improving personal safety and building integrity across various engineering applications.

A tailor-made blue organic emitter with hot exciton and aggregation-induced emission characteristics serves as a sensitizer in the innovative sensitizing system with a dual-channel stepwise energy transfer feature. The established material and device approach enables efficient, stable blue organic light-emitting diodes with narrow emission and low-efficiency roll-off at high luminance.

Marching toward next-generation ultrahigh-definition and high-resolution displays, the development of high-performance blue organic light-emitting diodes (OLEDs) with narrow emission and high luminance is essential and requires conceptual advancements in both molecular and device design. Herein, a blue organic emitter is reported that exhibits hot-exciton and aggregation-induced emission characteristics, and use it as a sensitizer in the proposed triplet–triplet annihilation (TTA)-assisted hot-exciton-sensitized fluorescence (HSF) device, abbreviated THSF. Results show that through dual-channel stepwise Förster and Dexter energy transfer processes, the THSF system can simultaneously enhance exciton utilization, accelerate exciton dynamics, and reduce the concentration of triplet excitons. The smooth management of excitons makes the overall performance of the THSF device superior to the control TTA fluorescence and HSF devices. Furthermore, a high-performance narrowband blue (CIEx,y = 0.13, 0.12) OLED is achieved using a two-unit tandem device design, providing an excellent maximum external quantum efficiency of 18.3%, a record-high L 90% (the luminance where the ƞ ext drops to 90% of its peak value) of ≈20 000 cd m−2, and a long half-lifetime at 100 cd m−2 initial luminance of ≈13 256 h. These results showcase the great potential of the THSF strategy in realizing efficient and stable blue OLEDs with narrow emission and high luminance.

This work developed a LiC6@Li counter electrode, as an alternative to Li metal for more precisely evaluating the electrochemical behavior of electrode materials at low temperatures. The low interfacial resistances facilitate preferential de-intercalation of Li+ from LiC6, resulting in a sharp decreased over-potential at low temperatures. Meanwhile, the rapid replenishment of Li+ through the solid–solid-connection reaction maintains stable LiC6@Li potential.

Li metal, as a counter electrode, is widely used for electrode materials evaluation in coin type half-cells. However, whether this configuration is suitable for different working conditions has often been neglected. Herein, the large resistance and high cathodic/anodic over-potential of Li metal at low temperature are highlighted, revealing its incompetence as counter electrode on cryogenic condition. In view of this, a novel LiC6@Li composite electrode is developed as a promising substitution for electrode materials evaluation. In the LiC6@Li electrode, Li+ de-intercalated from LiC6 preferentially due to the low interface resistance of LiC6, presenting a cathodic/anodic over-potential of 0.05 V (67 µA cm−2) at −20 °C, which is ten times lower than that of Li metal. Moreover, the rapid lithium replenishment into LiC6 from Li metal enables a stable potential of LiC6@Li. Consequently, the LiC6@Li-based half-cells enabled more precise evaluation of the Li+ storage potential and specific capacities of a series of electrode materials at low temperature. As an extension, KC8@K is also successfully prepared as a superior counter electrode to K metal. This work proposes a suitable counter electrode for more accurately evaluating electrode materials at subfreezing scenarios, demonstrating the necessity of specialized electrode evaluation systems for particular operating conditions.

The fabricated oriented chitosan nanofibrillar hydrogels (O-CN gels), via the synergy strategy of protein templating and mechanical training, achieve cartilage-like structure and mechanical performances, as well as high-water retention similar to cartilage. The resulting O-CN gels has excellent prospects in load-bearing cartilage engineering application.

Cartilage, as a load-bearing tissue with high-water content, exhibits excellent elasticity and high strength. However, it is still a grand challenge to develop cartilage-adaptive biomaterials for replacement or regeneration of damaged cartilage tissue. Herein, protein templating and mechanical training is integrated to fabricate crystal-mediated oriented chitosan nanofibrillar hydrogels (O-CN gels) with similar mechanical properties and water content of cartilage. The O-CN gels with an ≈74 wt% water content exhibit high tensile strength (≈15.4 MPa) and Young's modulus (≈24.1 MPa), as well as excellent biocompatibility, antiswelling properties, and antibacterial capabilities. When implanted in the box defect of rat's tails, the O-CN gels seal the cartilage (annulus fibrosus) defect, maintain the intervertebral disc height and finally prevent the nucleus herniation. This synergy strategy of protein templating and mechanical training opens up a new possibility to design highly mechanical hydrogels, especially for the replacement and regeneration of load-bearing tissues.

A novel composite proton exchange membrane (PEM) design that leverages carboxylic acid-functionalized polymers of intrinsic microporosity (cPIM-1) and polyvinylpyrrolidone (PVP). Harnessing Lewis acid-base interactions enables the development of a synergistic microporous structure that confines phosphoric acid clusters, enhancing proton conductivity and durability. This work addresses critical challenges in PEM development, while proposing a solutionfor the design of next-generation membranes.

High-temperature proton exchange membrane fuel cells (HT-PEMFCs) is regarded as a promising energy conversion system owing to simplified water management and enhanced tolerance to fuel impurities. However, phosphoric acid (PA) leaching remains a critical issue, diminishing energy density and durability, posing significant obstacle to the commercial development of HT-PEMFCs. To address this, composite membranes incorporating the carboxylic acid-modified polymer of intrinsic microporosity (cPIM-1) are designed as framework polymer, blended with polyvinylpyrrolidone (PVP) for HT-PEMFCs. The Lewis acid-base interactions between cPIM-1 and PVP created an extensive hydrogen-bonding network, improving membrane compatibility. The optimized microporous structure and multiple anchoring sites gave rise to “domain-limited” PA clusters, enhancing the capillary effect. Simultaneously, improved hydrophobicity synergistically optimizes catalytic interface, promoting continuous and stable proton transfer. The HT-PEMFCs based on PVP/cPIM-1 composite membrane achieved a peak power density of 1090.0 mW cm−2 at 160 °C, representing a 152% improvement compared to PVP/PES membrane. Additionally, it demonstrated excellent durability, with a voltage decay of 0.058 mV h−1 over 210 h of accelerated stress test corresponds to more than 5000 h of constant current density durability test. This study presents a promising strategy for the development of high-performance and durable novel membranes in various energy conversion systems.

Arylboronic acids are explored for use in the electrolyte engineering of Li─S batteries. The theoretically and experimentally verified coordination and mediation chemistry of arylboronic acids can not only stabilize the anode interface but also accelerate the sluggish sulfur conversion. 3,5-bis(trifluoromethyl)phenylboronic acid (BPBA) is chosen as a suitable electrolyte modifier, significantly improving the electrochemical performance of Li─S batteries.

Lithium-sulfur (Li─S) batteries offer a promising avenue for the next generation of energy-dense batteries. However, it is quite challenging to realize practical Li─S batteries under limited electrolytes and high sulfur loading, which may exacerbate problems of interface deterioration and low sulfur utilization. Herein, the coordination and mediation chemistry of arylboronic acids that enable energy-dense and long-term-cycling Li─S batteries is proposed. The coordination chemistry between NO3 − and arylboronic acids breaks the resonance configuration of NO3 − and thermodynamically promotes its reduction on the anode, contributing to a mechanically robust interface. The mediation chemistry between lithium arylborate and polysulfides distorts S─S/Li─S bonds, alters the rate-determining step from Li2S4→Li2S2 to Li2S6→Li2S4, and homogeneously accelerates the sulfur redox kinetics. Li─S batteries using 3,5-bis(trifluoromethyl)phenylboronic acid (BPBA) show excellent cycling stability (1000 cycles with a low capacity decay rate of 0.033% per cycle) and a high energy density of 422 Wh kg−1 under aggressive chemical environments (high sulfur loading of 17.4 mg cm−2 and lean electrolyte operation of 3.6 mL gS −1). The basic mechanism of coordination and mediation chemistry can be extended to other arylboronic acids with different configurations and compositions, thus broadening the application prospect of arylboronic acids in the electrolyte engineering of Li─S batteries.

Sub-nanowires organohydrogels featuring a dual-phase structure are fabricated through the simple mixing of hydroxyapatite sub-nanowires with organic solvent and aqueous phase, directly forming a stable water-in-oil structure. The organohydrogels inherently possess rapid self-healing ability, exhibit specific temperature-responsive behavior, and are broadly compatible with a variety of organic solvents and polymers.

Organohydrogels have significant applications in numerous fields. The current synthetic strategies generally rely on the intricate and complex design of lipophilic or hydrophilic polymers to achieve the goal of oil-water interpenetration. Herein, sub-nanowires organohydrogels with a dual-phase structure are fabricated by simply mixing hydroxyapatite sub-nanowires with organic solvent and aqueous phase. The sub-nanowires in the oil phase provide structural support, while surfactants in the sub-nanowires exist at the interface between oil and water, thus forming the water-in-oil structure. The organohydrogels possess commendable mechanical properties, an inherent self-healing ability, and a specific temperature-responsive behavior. Moreover, the organohydrogels are compatible with a variety of organic solvents and polymers, reserving the promise for wide-range applications in the future.

The rational toughening of photosensitive films is crucial for the development of flexible organic solar cells. Herein, a fine-grain strengthening strategy is demonstrated for mitigating the excessive aggregation or crystallization in small-molecule acceptor films, thereby suppressing the non-ideal thermodynamic behavior and residual-enriched state. Thus, these provide the potential for the synergistic enhancement of efficiency, mechanical and environmental stability in organic photovoltaics.

The rational toughening of photosensitive films is crucial for the development of robust and flexible organic solar cells (F-OSCs), which are always influenced by mechanical strain and thermodynamic relaxation within the films. Nevertheless, the potential determinants of these properties and quantitative metrics modulating the overall performance of flexible devices have not been thoroughly defined. Herein, a fine-grain strengthening strategy is demonstrated for mitigating the excessive aggregation or crystallization in small-molecule acceptor films, the secondary thermal relaxation of side chains in polyethylene oxide (PEO) local motion restricts the free fluctuation volume through hydrogen-bonding interactions, thereby suppressing the non-ideal thermodynamic behavior and residual-enriched state. These contribute to an increase in yield strength and a reduction in microcracks while enhancing the fracture energy at the donor/acceptor interface. Finally, the optimal F-OSCs demonstrate champion PCEs of 19.12% (0.04 cm2) and 16.92% (1.00 cm2), and maintain 80% of their initial efficiency after heating at 85 °C for 2600 h. Besides, the flexibility and mechanical robustness of devices are also optimized, the elastic modulus and stiffness are decreased by 50.68% and 5.71%. This work provides interesting references for the synergistic enhancement of efficiency, mechanical and environmental stability in flexible organic photovoltaics.

Interfacial adsorption layers based on N,N-bis(2-hydroxyethyl)glycine (BHEG) are constructed to inhibit Zn corrosion and polyiodide shuttle by employing an electrolyte additive strategy. These layers stabilize Zn anode via creating a “H2O-deficient” inner Helmholtz plane (IHP) and buffering the interfacial pH, while hindering polyiodide migration at the I2 cathode through ion–dipole interactions. Attributing to these benefits, a long-lasting aqueous Zn–I2 battery is realized.

Aqueous zinc–iodine (Zn–I2) batteries are promising candidates for large-scale energy storage due to the merits of low cost and high safety. However, their commercial application is hindered by Zn corrosion and polyiodide shuttle at I2 cathode. Herein, N,N-bis(2-hydroxyethyl)glycine (BHEG) based interfacial adsorption layers are constructed to stabilize Zn anodes and mitigate polyiodide shuttle according to ion–dipole interactions, by using a strategy of electrolyte additive. The tertiary amine (N(CH2)3) and carboxyl (─COO−) groups in the deprotonated BHEG can reversibly capture H+ and dynamically neutralize OH− ions, efficiently buffering the interfacial pH of Zn metal anodes and suppressing hydrogen evolution reactions. Additionally, the BHEG adsorption layers can repel 39.3% of H2O molecules at the Zn interface, creating a “water-deficient” inner Helmholtz plane and preventing Zn corrosion. Significantly, the N(CH2)3 groups in BHEG also inhibit polyiodide shuttle at the I2 cathode, which exhibits high adsorption energies of −0.88, −0.41, and −0.39 eV for I−, I2, and I3 −, respectively. Attributing to these benefits, the Zn–I2 battery can achieve a high areal capacity of 2.99 mAh cm−2 and an extended cycling life of 2,000 cycles, even at a high mass loading of I2 cathode (≈21.5 mg cm−2).

Responsive molecules are essential for organic in-sensor computing devices. This Review highlights recent advances in thedesign, synthesis, and incorporation of electrically, optically, and magnetically responsive molecules in multifunctional synaptic perception devices endowedwith both nonvolatile and volatile memory diversification. By exploiting the multifunctional nature of molecular switches, complex logic operations can be accomplished, bringing molecule-based neuromorphic computing closer to become a real technology.

In the brain, both the recording and decaying of memory information following external stimulus spikes are fundamental learning rules that determine human behaviors. The former is essential to acquire new knowledge and update the database, while the latter filters noise and autorefresh cache data to reduce energy consumption. To execute these functions, the brain relies on different neuromorphic transmitters possessing various memory kinetics, which can be classified as nonvolatile and volatile memory. Inspired by the human brain, nonvolatile and volatile memory electronic devices have been employed to realize artificial neural networks and spiking neural networks, respectively, which have emerged as essential tools in machine learning. Molecular switches, capable of responding to electrical, optical, electrochemical, and magnetic stimuli, display a disruptive potential for emulating information storage in memory devices. This Review highlights recent developments on responsive molecules, their interfacing with low-dimensional nanostructures and nanomaterials, and their integration into electronic devices. By capitalizing on these concepts, a unique account of neurotransmitter-transfer electronic devices based on responsive molecules with ad hoc memory kinetics is provided. Finally, future directions, challenges, and opportunities are discussed on the use of these devices to engineer more complex logic operations and computing functions at the hardware level.

This study introduces a novel programmable encryption strategy with controllable DNA synthesis and sequential encoding. The proposed hairpin-mediated primer exchange reaction (HAMER) system enables the dynamic generation of DNA sequences and the secure recording of information with user-specific access. This approach enhances data security, positioning DNA as a high-performance material to meet future confidentiality, integrity, and availability demands.

DNA molecules, with highly variable sequences and inherent programmability, emerge as a promising material for next-generation information storage and data encryption. However, due to the singular encryption method or limited randomness of the secret key, current encryptions remain vulnerable to brute-force attacks and the need for enhanced information security persists. This study introduces a programmable encryption strategy based on long-chain DNA synthesis and sequential encoding. The proposed hairpin-mediated primer exchange reaction (HAMER) system enables the generation of DNA keys and the recording of encoded information. Ultimately, encrypted text and image data can be decoded and retrieved through sequencing with customized access based on user permissions. This approach positions DNA as a high-performance information material and establishes a programmable encryption framework, offering strong potential to meet the confidentiality, integrity, and availability demands of future information security systems.

A fully synthetic active liquid crystal, energized by an acoustic field, is presented. This system exhibits active nematic behavior, tunable topological defect dynamics, and persistent hydrodynamic vortices at high activity levels. The material maintains stable properties while enabling precise activity control in a wide range.

Active nematic materials combine orientational order with activity at the microscopic level. Current experimental realizations of active nematics include vibrating elongated particles, cell layers, suspensions of elongated bacteria, and a mixture of bio-filaments with molecular motors. The majority of active nematics are of biological origin. The realization of a fully synthetic active liquid crystal comprised of a lyotropic chromonic liquid crystal energized by ultrasonic waves, is reported. This synthetic active liquid crystal is free from biological degradation and variability, exhibits phenomenology associated with active nematics, and enables precise and rapid activity control over a significantly extended range. It is demonstrated that the energy of the acoustic field is converted into microscopic extensile stresses disrupting long-range nematic order and giving rise to an undulation instability and proliferation of topological defects. The emergence of unconventional free-standing persistent vortices in the nematic director field at high activity levels is revealed. The results provide a foundation for the design of externally energized active liquid crystals with stable material properties and tunable topological defect dynamics crucial for the realization of reconfigurable microfluidic systems.

Implantable devices rely on batteries that demand surgical replacement, posing risks, and financial burdens. Ultrasound energy transfer (US-ET) offers a revolutionary wireless alternative but struggles with efficiency. The presented dielectric-ferroelectric-boosted US-TENG (US-TENGDF-B) is thin, flexible, and biocompatible that provides high-efficiency and stable power delivery in curved positions, fostering a future of noninvasive and sustainable wireless energy transfer solutions for biomedical applications.

Wireless powering of rechargeable-implantable medical devices presents a challenge in developing reliable wireless energy transfer systems that meet medical safety and standards. Ultrasound-driven triboelectric nanogenerators (US-TENG) are investigated for various medical applications, including noninvasive percutaneous wireless battery powering to reduce the need for multiple surgeries for battery replacement. However, these devices often suffer from inefficiency due to limited output performance and rigidity. To address this issue, a dielectric-ferroelectric boosted US-TENG (US-TENGDF-B) capable of producing a high output charge with low-intensity ultrasound and a long probe distance is developed, comparatively. The feasibility and output stability of this deformable and augmented device is confirmed under various bending conditions, making it suitable for use in the body's curved positions or with electronic implants. The device achieved an output of ≈26 V and ≈6.7 mW output for remote charging of a rechargeable battery at a 35 mm distance. These results demonstrate the effectiveness of the output-augmented US-TENG for deep short-term wireless charging of implantable electronics with flexing conditions in curved devices such as future total artificial hearts.

This study presents an anisotropic inductive liquid metal sensor (AI-LMS) inspired by the biomechanical properties of human fingertips. The AI-LMS demonstrates superior performance in multidimensional pressure sensing, characterized by high linearity and stability. Potential applications encompass enhancing robotic tactile perception and facilitating precise 3D surface scanning, representing a significant milestone in the field of soft robotics technology.

The advancement of robotic behavior and intelligence has led to an urgent demand for improving their sensitivity and interactive capabilities, which presents challenges in achieving multidimensional, wide-ranging, and reliable tactile sensing. Here an anisotropic inductive liquid metal sensor (AI-LMS) is introduced inspired by the human fingertip, which inherently possesses the capability to detect spatially multi-axis pressure with a wide sensing range, exceptional linearity, and signal stability. Additionally, it can detect very small pressures and responds swiftly to prescribed forces. Compared to resistive signals, inductive signals offer significant advantages. Further, integrated with a deep neural network model, the AI-LMS can decouple multi-axis pressures acting simultaneously upon it. Notably, the sensing range of Ecoflex and PDMS-based AI-LMS can be expanded by a factor of 4 and 9.5, respectively. For practical illustrations, a high-precision surface scanning reconstruction system is developed capable of capturing intricate details of 3D surface profiles. The utilization of biomimetic AI-LMS as robotic fingertips enables real-time discrimination of diverse delicate grasping behaviors across different fingers. The innovations and unique features in sensing mechanisms and structural design are expected to bring transformative changes and find extensive applications in the field of soft robotics.

The study investigates the effects of nanoplastics on human immune cells using palladium-doped polystyrene nanoplastics and mass cytometry. It reveals that nanoplastics accumulate in various immune cell subpopulations, reducing cell viability and impairing function. In vivo experiments in mice confirm their accumulation in several immune cells. This accumulation poses health risks, highlighting the potential dangers of nanoplastics to human health.

The increasing exposure to nanoplastics (NPs) raises significant concerns for human health, primarily due to their potential bioaccumulative properties. While NPs have recently been detected in human blood, their interactions with specific immune cell subtypes and their impact on immune regulation remain unclear. In this proof-of-concept study, model palladium-doped polystyrene NPs (PS-Pd NPs) are utilized to enable single-cell mass cytometry (CyTOF) detection. The size-dependent impact of carboxylate polystyrene NPs (50–200 nm) is investigated across 15 primary immune cell subpopulations using CyTOF. By taking advantage of Pd-doping for detecting PS-Pd NPs, this work evaluates their impact on human immune-cells at the single-cell level following blood exposure. This work traces PS-Pd NPs in 37 primary immune-cell subpopulations from human blood, quantifying the palladium atom count per cell by CyTOF while simultaneously assessing the impact of PS-Pd NPs on cell viability, functionality, and uptake. These results demonstrate that NPs can interact with, interfere with, and translocate into several immune cell subpopulations after exposure. In vivo distribution experiments in mice further confirmed their accumulation in immune cells within the liver, blood, and spleen, particularly in monocytes, macrophages, and dendritic cells. These findings provide valuable insights into the impact of NPs on human health.

Biological Tissue Microstructures

The Morpho butterfly wing is a natural photonic crystal that interacts selectively with polarized light. Lisa V. Poulikakos and co-workers interface the Morpho wing with breast cancer tissue sections and illuminate the system with polarized light for quantitative, contact- and stain-free assessment of tissue microstructures. This imaging approach enables improved understanding of the role of tissue microstructure in the origin and progression of disease. More details can be found in article number 2407728.

Lignocellulose-Mediated Functionalization of Liquid Metals Composites

In article number 2415761, Wei Li, Liyu Zhu, Ying Xu, Guanhua Wang, Ting Xu, and Chuanling Si summarize the state-of-the-art of lignocellulose-based liquid metals materials for the frontiers of multifunctional materials and discuss how to design and functionalize lignocellulose-based liquid metals materials with specific performance. The cover image shows a lignocellulose-based liquid metals materials for the frontiers application.

Heterogeneous Integration of Wide Bandgap Semiconductors and 2D Materials

The heterogeneous integration of 2D materials and WBG enables the growth of high-quality WBG films and the 2D material-assisted layer transfer of them, facilitating flexible electronics and micro- LEDs. This cover image illustrates the transfer process of WBG/2D heterostructures and their potential applications in HEMTs and micro-LEDs. More details can be found in article number 2411108 by Soo Ho Choi, Yongsung Kim, Il Jeon, and Hyunseok Kim.

Nanomedicine Accumulation

Accurate prediction of nanomedicine accumulation is crucial for guiding patient stratification and optimizing treatment strategies in precision medicine. In article number 2416696, Shouju Wang and colleagues present an interpretable radiomics model capable of predicting nanomedicine tumor accumulation using routine medical imaging, achieving an impressive accuracy of 0.851. This study demonstrates the potential of noninvasive imaging for patient stratification and the precise tailoring of nanomedicine therapies, paving the way for more personalized and effective cancer treatment.