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We investigate photon transport in magnetically tunable fluids, specifically magnetic nanofluids and magnetorheological fluids (MRFs). Our study focuses on the statistical analysis of light transport in these fluids, with a particular focus on earlier theoretical proposals related to the possibility of Anderson localization in these systems. We employ a well-known mesoscopic quantifier, the generalized conductance, to assess the domain of light transport in these systems. Magnetic nanofluids, which contain nanometer-sized magnetite particles, exhibit weak scattering with no substantial consequence on conductance, regardless of the applied magnetic field. In contrast, magnetorheological fluids, a bidispersion of micrometer-sized magnetizable spheres in a magnetic nanofluid, show a decrease in conductance to values below unity as the magnetic field strength increases. This decrease occurs at the magnetic-field-induced photonic bandgap in MRFs, which plays a crucial role in the localization process and is characterized by reduced transmitted intensity, altered speckle patterns, and significant changes in intensity statistics. Our findings also highlight the temporal evolution of field-induced speckles, where the initial high correlation decreases over time, and the correlation width widens indicating that the duration of sustained correlation enhances as the system reaches equilibrium. Consequently, the evolution of field-induced scatterers in MRFs significantly emulates light localization effects as the system attains equilibrium. This study concludes that our system is a prime candidate to observe possible strong localization in a magnetically tunable, dissipative complex system. Such systems hold potential applications in optical switching, adaptive optics, and smart materials design through controlled light manipulation using external magnetic fields. [ABSTRACT FROM AUTHOR]

To design smart microwave-absorbing materials (MAMs), it is essential to adjust the corresponding electrical conductivity and dielectric parameters according to variable conditions. However, it is still challenging to concurrently adjust the effective absorbing intensity and frequency range in MAMs due to their interdependent constraints. Here, we developed intelligent MAMs by incorporating core–shell structure vanadium dioxide @ polydopamine (VO2@PDA) powders as polarization loss units, while the subwavelength-sized reduced graphene oxide microspheres (RGOms) were used as conduction loss units. When the temperature is higher than the metal–insulator phase transition temperature of the insulator state VO2 (M), the corresponding metal state VO2 (R) could be produced, which, therefore, contributes to an enhanced interfacial polarization loss due to the significant electrical performance differences between the VO2 (R) and the PDA shell. As an optimized result, the changes of the effective absorption frequency band (▵EAF) and reflection loss (▵RL) of the RV3 composite could be approximately 1.5 GHz and 24 dB, respectively, attributable to the phase transition of VO2. This study provides a novel approach for the adjustment of electromagnetic responses based on dynamic interfacial polarization performance, which offers broader prospects for developing next-generation smart electromagnetic absorption devices with both reversible microwave absorption frequency range and intensities. [ABSTRACT FROM AUTHOR]

FCC-HCP phase transition plays a pivotal role in many intelligent materials, which also occurs in Pb under high pressures. However, its impacts on the spallation of polycrystalline, as well as the effects related to grain size, are still unclear. In this work, spallation behaviors of Pb polycrystals with different grain sizes under various shock loadings are investigated using the quasi-coarse-grained molecular dynamics (QCGD) method based on our recently developed response embedding atom model potential. The QCGD method is rigorously validated for applications in the metals exhibiting solid–solid phase transitions. Due to the restriction of the critical size for the phase transition nucleus, the coarsening level of the QCGD method cannot exceed two times the lattice parameter. Nevertheless, such a method enables us to explore the whole rule of the grain-size-dependence incipient spall strength. Our results suggest that the incipient spall strength exhibits a transition from the Hall–Petch to the inverse Hall–Petch relationship at about 13 nm and the spallation strength converging to that of a single crystal for grain sizes larger than 60 nm. As the grain size decreases, void nucleation becomes more prevalent than void growth, making the material better equipped to prevent the progression of damage into fractures. When the grain size is sufficiently large, voids nucleate and grow in the grain interior, making the spallation behave like in a single crystal. Interestingly, the phase transition from HCP to FCC phase enhances dislocation entanglement, leading to heterogeneous nucleation of voids in the grain interior. [ABSTRACT FROM AUTHOR]

We designed a trigonal symmetric imine-linked covalent organic framework (COF), TFPC-DAB, with control over the angularity of the building units, where a bent C2-symmetric diamine, such as 1,3-diaminobenzene (1,3-DAB or DAB), with an exo-angle of 120° was used instead of those with an exo-angle of 180°, in combination with a C3-symmetric trialdehyde, such as tri(4-formylphenoxy)cyanurate (TFPC). Its synthesis was accomplished by reacting the building units in a mixture of mesitylene/dioxane/6 M acetic acid under solvothermal conditions. The phase purity, thermal stability, and porosity of TFPC-DAB were established by various analytical techniques. Utilizing the Density Functional Tight Binding (DFTB+) simulation and Pawley refinement, the best fit of the small angle x-ray pattern was found to have an AA stacking of TFPC-DAB in the trigonal space group P3 with low refinement parameters. Such smart materials are in huge demand to detect hazardous corrosive chemicals, such as HCl and NH3. The dual features of electron deficient π-acidic triazine moiety and heteroatoms (N/O) from TFPC and electron rich phenyl units from DAB embodied in the framework enhance its luminescent property and thereby make it suitable for solvent-based HCl and NH3 sensing. The detection limits for HCl and NH3 in methanol were found to be 14 and 82 ppb, respectively. The effect of solvent polarity on the sensing studies was observed with much lower detection limits in dioxane: 2.5 and 11 ppb for HCl and NH3, respectively. A detailed theoretical calculation using density functional theory and configurational bias Monte Carlo modules was conducted for understanding interactions between the COF and HCl or NH3 analytes. [ABSTRACT FROM AUTHOR]

Intelligent materials are used to create novel biomaterials that can recognize and respond to environmental cues, as well as perform specific tasks for modern medicine and sustainability. There are a wide range of applications for intelligent biomaterials, from ecological restoration to health. In reaction to physical, chemical, and biological stimuli, intelligent biomaterials can change their properties. Hydrogels have garnered a lot of attention and the incorporation of decellularized tissues into the hydrogel synthesis process exhibits a number of benefits. The development of smart/intelligent response polymeric biomaterials for novel biomedical applications is the focus of this review. [ABSTRACT FROM AUTHOR]

Crystalline materials are traditionally known for their brittleness when subjected to external stress. However, recent advancements have enabled the creation of flexible crystals through specific molecular architectures. These innovative materials can deform in response to light or mechanical stress, making them promising candidates for smart materials, sensors, actuators, and optoelectronic devices. While considerable research has been conducted on the effects of individual external stresses, the investigation of flexible crystals that respond to multiple stimuli and their bending mechanisms remains to be improved. This review aims to elucidate the mechanisms that govern the flexibility of crystals responsive to both light and mechanical stimuli. We will analyze the mechanical properties related to 1D or 2D assembly, [2 + 2] or [4 + 4] photodimerization, and molecular isomerization and provide insights on designing new molecular structures to enhance the flexibility of crystals. Additionally, we will address current challenges in the field and propose future research directions to advance the development of flexible molecular crystals. [ABSTRACT FROM AUTHOR]

An approach for optimizing the poling conditions of metal matrix piezoelectric composite (MMPC) using a series capacitor model is proposed and its verification is performed. The oxide film formed around the electrodes in MMPC is necessary for insulation between the electrodes and the metal matrix, however, during the poling process, the oxide film deprives the polarizing electric field and prevents polarization of piezoelectric ceramics. Therefore, a method to optimize the polarizing voltage using the thickness and dielectric constant of the oxide film in a series capacitor model with a simplified structure of the MMPC is required. In addition, the validity of the proposed method is investigated by output voltage obtained from fabricated composites that performed the poling process. The results of the optimization show that optimal polarization is not possible with the Ni and Ti oxide films used in this study. However, the results of the polarization treatment of the actual composite material confirmed the validity of the proposed method, as the output voltage improvement is in line with the proposed method. [ABSTRACT FROM AUTHOR]

Modern society demands transitioning to sustainable agriculture to alleviate environmental effects. Traditional nitrogen fertilizers, like urea, lead to undesirable leaching, runoff losses, and low nutrient use efficiency in crops upon contact with water. Controlled‐release fertilizers (CRFs) present a promising solution by mitigating nutrient loss and enhancing plant uptake. However, concerns arise with synthetic polymer‐coated fertilizers, as they may not degrade in soil and can impact microbial activity. This review focuses on bio‐based coatings for CRFs, summarizing their performance over the past decade in the release properties in water and soil, water retention, biodegradability, and evaluating their efficacy in greenhouse and field trials. Additionally, the review explores innovative strategies for smart coating materials in CRF development, including pH‐sensitive, thermos‐sensitive, enzymatic‐sensitive, and self‐healing technologies. This critical evaluation aims to promote the development of more effective and sustainable fertilizers for agriculture. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of ordered arrangement of MXene in hydrogel on its conductivity of hydrogel was investigated in detail. • The gradient structure in synergy with the thermal sensitive MXene nanolayer contributed to the excellent actuation ability of the hydrogel. • The hydrogel was able to rival commercial electrodes to detect Pulse and ECG signals. Smart sensing and excellent actuation abilities of natural organisms have driven scientists to develop bionic soft-bodied robots. However, most conventional robots suffer from poor electrical conductivity, limiting their application in real-time sensing and actuation. Here, we report a novel strategy to enhance the electrical conductivity of hydrogels that integrated actuation and strain-sensing functions for bioinspired self-sensing soft actuators. Conductive hydrogels were synthesized in situ by copolymerizing MXene nanosheets with thermosensitive N -isopropylacrylamide and acrylamide under a direct current electric field. The resulting hydrogels exhibited high electrical conductivity (2.11 mS/cm), good sensitivity with a gauge factor of 4.79 and long-term stability. The developed hydrogels demonstrated remarkable capabilities in detecting human motions at subtle strains such as facial expressions and large strains such as knee bending. Additionally, the hydrogel electrode patch was capable of monitoring physiological signals. Furthermore, the developed hydrogel showed good thermally induced actuation effects when the temperature was higher than 30 °C. Overall, this work provided new insights for the design of sensory materials with integrated self-sensing and actuation capabilities, which would pave the way for the development of high-performance conductive soft materials for intelligent soft robots and automated machinery. [ABSTRACT FROM AUTHOR]

Intelligent materials demonstrate promising applications in switchable oil/water separations. A stearic acid (SA) hydrophobically modified SiO2 coating (SA/SiO2) with switchable wettability was developed by simply spraying. The SA/SiO2 coating with micro-nanostructure showed excellent superhydrophobicity with water contact angle (WCA) and oil contact angle (OCA) of 158.7° and 0°, respectively. When the SA/SiO2 coating was contacted with ammonia, it showed excellent superhydrophilicity, with WCA and underwater oil contact angle of 0° and 155.4°, respectively. After heating treatment, the SA/SiO2 coating returned to superhydrophobicity. Through wettability switching, the prepared SA/SiO2 coating could be applied for on-demand separation of oil/water/oil ternary mixtures as well as various water-in-oil emulsions and oil-in-water emulsions, and the separation efficiency of oil-in-water emulsion could reach up to 99.97%, accompanied by a high flux at the same time. More importantly, the SA/SiO2 coating exhibited significant robustness and excellent reusability, which maintained a superior separation efficiency of over 99.80% after 10 cycles emulsion separation, suggesting its promising potential for oily wastewater treatment. The simple and environmentally friendly coating preparation method as well as easy implementation of response conditions and short switching time provide a reference for the preparation of intelligent response oil/water separation materials. [ABSTRACT FROM AUTHOR]

Smart materials enabling emission intensity or wavelength tuning by light stimulus have attracted attention in cutting‐edge fields. However, due to the general limitation of the dense molecular stacking (in solid states, especially in crystals) on photoresponsivity, constructing rapidly phototunable solid‐state luminescent systems remains challenging. Herein, we present a new luminophore that serves as both a photoresponsive and a luminous group with enhanced conformational freedom to attain this goal, namely, relying on photoexcitation‐induced molecular conformational change of an ionized persulfurated arene based on weak intermolecular aliphatic C−H⋅⋅⋅π interaction. Together with the phosphorescence characteristic of the molecule itself, rapidly enhanced phosphorescence upon irradiation can be observed in a series of phase states, like solution state, crystal, and amorphous state, especially with a high photoresponsive rate of 0.033 s−1 in crystal state that is superior to the relevant reported cases. Moreover, a rapidly phototunable afterglow effect is achieved by extending this molecule into some polymer‐based doping systems, endowing the system with unique dynamic imaging and fast photopatterning capabilities. This single‐luminophore molecular engineering and underlying mechanism have implications for building other condensed functional materials, principally for those with stimuli responses in solid states. [ABSTRACT FROM AUTHOR]

The soft actuators of smart materials have attracted significant attention in recent years due to their unique functions and distinctive characteristics. The actuators are composed of smart materials that can demonstrate substantial alterations in their dimensions, shape, or mechanical characteristics when subjected to external stimuli, including but not limited to temperature, light, electricity, or magnetic fields. These aforementioned characteristics render them highly advantageous for various applications, including tissue engineering, prosthetics, surgical robots, drug delivery, and soft robotics. A deeper understanding of the principles of the actuators is crucial for their development and application expansion. This article provides a comprehensive analysis of soft actuators made from smart materials, explaining their underlying concepts, operational mechanisms, material composition, production techniques, and the diverse range of applications across various fields, including tissue engineering, prosthetics, surgical robotics, drug delivery systems, and the emerging field of soft robotics. This review further highlights the current challenges and prospects to address these problems to enable their ability to revolutionize into a variety of different technical fields. [ABSTRACT FROM AUTHOR]

[Display omitted] • Janus bilayer hydrogel actuators powered by ionic fuels were prepared. • The use of ionic fuels solves the problem of waste accumulation. • Actuators exhibit tunable bending and cyclic actuations with minimal damping. • Programmable and flexible soft robotics were developed for versatile tasks. • This breakthrough advances adaptive materials and soft robotics technologies. Hydrogel actuators powered by chemical fuels are pivotal in autonomous soft robotics. Nevertheless, chemical waste accumulation caused by chemical fuels hampers the development of programmable and reusable hydrogel actuating systems. We propose the concept of ionic fuel-powered soft robotics which are constructed by programmable salt-responsive actuators and use waste-free ionic fuels. Herein, soft hydrogel actuators were developed by orchestrating the Janus bilayer hydrogels' capacity for swelling and shrinking. Decomposable and easily removable ionic fuels were applied to power the actuators. Swelling tests were used to evaluate the deformability of the hydrogels. Tensile tests were performed to investigate the modulus of the hydrogels. The bonded interface composed of the interpenetrating polymer chains from both hydrogel layers bilayer was evidenced by the optical microscopy and scanning electron microscopy. The ionic conductivities of solutions were determined by a conductivity meter. Furthermore, a range of biomimetic soft robots with various shapes and asymmetrical structures have been designed and fabricated to execute complex functions. The programmable actuators powered by ionic fuel exhibit adjustable bending orientations, amplitudes, and durations, along with consistent cyclic actuations enabled by replenishment of the fuel without noticeable loss in performance. Many life-like programmable soft robotic systems were designed, indicating spatiotemporally controllable functions. [ABSTRACT FROM AUTHOR]

Chitosan and collagen are two valuable biopolymers for the synthesis and design of biomaterials. In this work, we evaluate the effect of the concentration of chitosan on the physicochemical and biological properties of polyurethane‐crosslinked collagen hydrogels. Chitosan was added with a proportion ranging from 0 to 40 wt%. Depending on the aminoglycoside content, semi‐interpenetrating polymeric networks (semi‐IPNs) or completely IPNs were generated; this is attributed to the occlusion of the chitosan granules in the reticulated fibrillar matrix. The presence of chitosan in these hydrogels provides antibacterial capacity against pathogenic microorganisms such as Escherichia coli, which is corroborated by inhibition halo experiments. Hydrogels with 40 wt% of chitosan only showed improvement in the gelation time and mechanical performance, indicating a dependent relation of these properties with respect to the aminopolysaccharide content. Hydrogels with 10 wt% of chitosan showed the best biomedical performance. They also have the highest reticulation, swelling capability and chemical stability against degradation events such as hydrolysis and proteolysis. Further, they have the best biocompatibility for human monocytes, and they stimulate the secretion of monocyte chemotactic protein‐1 and tumor necrosis factor‐alpha. Also, these hydrogels showed a controlled release of ketorolac at pH 7 and 37 °C. The results of these in vitro biological tests demonstrate the potential application of novel biopolymer‐based hydrogels in chronic wound healing due to their antibacterial capacity and modulation of the biological response of specialized cells in dermal repair treatments, as well as for the design of smart materials for the controlled release of drugs. © 2023 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Smart windows can effectively balance the space temperature of buildings without compromising the essential functions of windows. However, conventional thermochromic windows have limited sunlight regulation capabilities and face challenges with switching as desired. Herein, A class of novel smart windows based on crystal hydrogels is introduced that achieve free switching between transparent (for heating) and opaque (for radiative cooling) states through thermal and mechanical stimuli. The crystal hydrogels are made from cross‐linked polyacrylamide (PAM) and sodium acetate (NaAc). By optimizing the sodium acetate concentration and sample thickness, The combination of excellent cooling ability is achieved at the opaque state and good low‐temperature stability at the transparent state in the hydrogels. Using the optimized hydrogel to prepare a smart window equipped with a heater and a mechanical trigger tip, the rapid on‐demand transition between transparent and opaque states is demonstrated. The results indicate that the smart window lowers temperatures by up to 9.4 °C compared to ordinary windows and maintains stable emissivity and reflectivity even after 100 cycles due to its robust solar modulation capabilities. This technology provides new energy‐saving solutions for smart buildings but also explores future applications of smart materials, showcasing innovative advantages and technical strengths in smart windows. [ABSTRACT FROM AUTHOR]

This paper had conducted tensile shear tests on single-lap joints (SLJs)bonded structures of carbon fiber reinforced resin matrix (CFRP) composite laminates with different overlap lengths, overlap widths, overlap model, adherend material, and adhesive layer thicknesses under two environments: room temperature dry state (RTD) and elevated temperature wet state (ETW). The failure modes were observed, and load–displacement curves were obtained. The microscopic morphology of the fracture surface was observed by scanning electron microscope (SEM). At the same time, a finite element simulation model was established to simulate the damage initiation and evolution process between layers and in the adhesive layer, and analyze the distribution laws of peel stress and shear stress in the adhesive layer. Through the combination of test data and simulation results, the influences of geometric parameters, material parameters and environmental parameters on the structure were explored, and the joint failure mechanism was revealed. Finally, the ACO-BP neural network was used to optimize the geometric parameters through test data. The research results showed that the geometric parameters of the structure mainly affect the bearing capacity and failure type. Reducing the overlap length and increasing the overlap width within a certain range can weaken the peeling phenomenon, so that a smaller overlap area has a higher shear strength. The material parameters of the adherend mainly affect the stress distribution law and stress transfer process of the adhesive layer in the overlap area. The joint mainly bore shear stress and peel stress, and shear stress is the main cause of damage initiation. When the types of adherend materials are different, the stress distribution law shows obvious asymmetric offset. The lap model mainly affects the location distribution of the failure area, and the environmental parameters mainly affect the area proportion relationship of various fracture forms in the mixed failure mode. [ABSTRACT FROM AUTHOR]

Shape memory alloys (SMAs) are widely used across various industries, including medicine, due to their inherent properties such as the shape memory effect, pseudo-elasticity, antigenicity, decomposition, biodegradability, biocompatibility, resistance to corrosion, and wear. This review article aims to cover different aspects of SMAs, including their fundamental concepts such as origin, exceptional properties, fabrication techniques, and structural analysis. Exploring the SMAs at the nanoscale using molecular dynamics analysis and recent studies that integrate machine learning techniques. Finally, the article concludes with a discussion of various applications of SMAs, considering the properties and potential fields of use. [ABSTRACT FROM AUTHOR]

Substrate transport within biological tissues is diverse, with the most fundamental process being transport across cell membranes, which plays a crucial role in sustaining life. In this study, an artificial substrate transport system based on hydrogels by utilizing molecular recognition and stimuli‐responsive substrates is developed. α‐ and β‐Cyclodextrins are selected as host molecules, while adamantane serves as the guest molecule, enabling the adhesion of two hydrogels through self‐assembly. Under light stimulation, the light‐responsive dye, azobenzene derivative, is transported between the two hydrogels. This research provides new insights into the development of light‐controlled substance transport systems, which can be applied to biological substance delivery and the creation of smart materials. [ABSTRACT FROM AUTHOR]

Although technologies and processes for creating smart composite structures have been established, significant limitations still necessitate additional research to overcome. Indeed, numerous studies have highlighted the challenges of embedding active elements, often leading to compromises in the structural integrity of smart composite materials. In contrast, this study introduces a novel perspective, offering innovative insights and valuable contributions to the existing knowledge. The primary contribution of this study lies in addressing the critical need for the seamless integration of active materials within composite structures. To demonstrate this, our study considers the potential integration of Polyvinylidene Fluoride (PVDF), a polymer-based piezoelectric material, with pre-impregnated unidirectional flax fibers to produce a smart composite structure. The consolidation molding process was adopted to manufacture the smart composite samples for investigations. Experimental analysis were then considered to evaluate the influence of the embedded PVDF film on the mechanical performance of the structure and to assess the resulting functional properties. X-ray micro-computed tomography and an additional strength-of-material test approach, Interlaminar Shear Strength (ILSS), were performed to explore the impact of the insertion on the integrity of the laminate structure. On the other hand, we conducted vibration tests to assess the electromechanical properties. The tomography results reveal void elimination in the edges of the active material insert, which could be attributed to the choice of thin film materials. Moreover, the ILSS results highlight the minimal impact of PVDF material on mechanical performance, showcasing a mere 0.69% degradation of the material strength. These results are comparable to the recently reported works but with an appreciable margin of improvement. The vibration test response demonstrates the ability of the embedded piezoelectric material to generate voltage, which validates our integration procedure. The smart composite material's sensitivity to ambient vibrations and its power generation potential show promise for sensing and energy harvesting. [ABSTRACT FROM AUTHOR]

Generative Artificial Intelligence (AI), characterized by its ability to generate diverse forms of content including text, images, video and audio, has revolutionized many fields, including medical education. Generative AI leverages machine learning to create diverse content, enabling personalized learning, enhancing resource accessibility, and facilitating interactive case studies. This narrative review explores the integration of generative artificial intelligence (AI) into orthopedic education and training, highlighting its potential, current challenges, and future trajectory. A review of recent literature was conducted to evaluate the current applications, identify potential benefits, and outline limitations of integrating generative AI in orthopedic education. Key findings indicate that generative AI holds substantial promise in enhancing orthopedic training through its various applications such as providing real-time explanations, adaptive learning materials tailored to individual student's specific needs, and immersive virtual simulations. However, despite its potential, the integration of generative AI into orthopedic education faces significant issues such as accuracy, bias, inconsistent outputs, ethical and regulatory concerns and the critical need for human oversight. Although generative AI models such as ChatGPT and others have shown impressive capabilities, their current performance on orthopedic exams remains suboptimal, highlighting the need for further development to match the complexity of clinical reasoning and knowledge application. Future research should focus on addressing these challenges through ongoing research, optimizing generative AI models for medical content, exploring best practices for ethical AI usage, curriculum integration and evaluating the long-term impact of these technologies on learning outcomes. By expanding AI's knowledge base, refining its ability to interpret clinical images, and ensuring reliable, unbiased outputs, generative AI holds the potential to revolutionize orthopedic education. This work aims to provides a framework for incorporating generative AI into orthopedic curricula to create a more effective, engaging, and adaptive learning environment for future orthopedic practitioners. [ABSTRACT FROM AUTHOR]

Fabricating photonic crystals (PCs) with dynamic multi‐stimuli‐responsive structural colors, recordable colors, and self‐healable properties is significant for their emerging applications, yet remains a big challenge. Here, an all‐in‐one multifunctional PC (MFPC) film with outstanding mechanochromic, thermochromic, solvatochromic, color/shape‐recordable, self‐healable, and adhesive functions is designed and prepared by simply non‐close‐assembling silica particles into the unique 2‐[[(Butylamino)carbonyl]oxy]ethyl acrylate (BCOEA) followed by photopolymerization. The success is mainly due to the rational combination of non‐close‐packing structures and BCOEA's characteristics, including its urethane groups with numerous sacrificial hydrogen bonds, temperature‐dependent refractive index, swellable and deformable polymer network, as well as low glass‐transition temperature. The MFPC's hue and color saturation can be reversibly and dynamically modulated by strain/pressure/solvents and temperature, respectively, thereby realizing visually and spectrally sensing these stimuli. More interestingly, the color‐responsiveness combined with other functions endows MFPCs with fascinating emerging applications, including multilayer optical filters, inkless printing, reconfigurable multicolor patterns, stretching‐based anti‐counterfeiting, etc. This work offers a new perspective for designing next‐generation smart photonic materials and will facilitate their all‐round applications. [ABSTRACT FROM AUTHOR]

Intrinsically stretchable devices often suffer from non‐uniform strain distributions under direct‐stretching conditions due to their large‐scale, patterned designs, leading to inconsistent performance. To address these issues, mechanochromic materials—substances that change color in response to strain—for precise and intuitive strain monitoring are employed. Leveraging this data, strategic design modifications, including extrinsic techniques such as rigid‐island with soft‐substrate and kirigami cuts are implemented, to mitigate strain non‐uniformity. Thus, highly desired uniform and homogenous strain control in a multi‐pixel stretchable system is achieved. By integrating these strain‐stopping with uniform strain control methods into arrays of rigid and soft chiral liquid crystal elastomers (CLCEs), effective color separation is demonstrated for encrypted information with enhanced strain uniformity and strain control. Additionally, the dynamic optical selectivity of circularly polarized light (CPL) of the CLCEs under specific conditions is explored, using uniaxial stretching to achieve both optical color changes and refined CPL separation. Consequently, leveraging the inherent optical properties of CLCEs, a uniform and highly functional multi‐pixel operating stretchable system is devised. The application of these extrinsic strain control strategies not only resolves issues of strain uniformity but also advances the field of stretchable smart materials, offering new possibilities for dynamic color‐ and polarization‐separating based on encrypted applications. [ABSTRACT FROM AUTHOR]

The self‐assembly of block copolymers (BCPs) into photonic materials has garnered increasing interest due to the versatility and ease of fabrication offered by the synthesized building blocks. BCPs are highly tunable, with their self‐assembled structures' size being adjustable by modifying the block lengths, molecular weight(Mw), and polymer composition. This review provides a concise summary of the use of BCPs as photonic pigments, which generate color through structural manipulation rather than relying on chemical pigmentation. These photonic crystal pigments manipulate light behavior, including interference, diffraction, and diffusion, to generate specific colors. BCPs are categorized into two types: linear block copolymers (LBCPs) and brush block copolymers (BBCPs), each involving different monomers that form photonic crystals(PCs). The structural evolution and advancements of BCPs in various practical applications are also explored. It concludes by suggesting that structural color(SC) pigments based on eco‐friendly PCs may replace traditional chemical ones in fields such as printing ink, biosensing, chemical sensing, and adaptive photonic materials. [ABSTRACT FROM AUTHOR]

In the field of intelligent manufacturing, flexible sensors play a key role as sensing components. However, people have previously focused on the normal response of tactile sensors and neglected the tangential response, and the traditional symmetric structure still has some difficulties in detecting the tangential force. Here, this work designed a novel sensor with high shear sensing capabilities using 3D printing technology to create micro‐pillar structures with adjustable aspect ratios, allowing for a wide detection range or high sensitivity. The sensor is composed of an anisotropic micro‐pillar dielectric layer and the fabric electrode layers. By vertically stacking two subunits, the sensor can accurately detect both the magnitude and direction of tangential forces. In addition, the sensor has virtually no signal drift after 20000 cycles, providing long‐term stability and durability. Finally, the sensor is integrated with AI technology and applied in areas such as robotic arm grasping, fabric texture sensing, and material recognition, highlighting its strong potential for applications in robotics and human‐machine interaction. [ABSTRACT FROM AUTHOR]

Smart dry adhesives, a rapidly growing class of intelligent materials and structures, are engineered to provide strong, robust adhesion when needed while also allowing for controlled, easy detachment in response to specific stimuli. Traditional smart adhesives, often exemplified by fibrillar structures made of elastomers, face a number of challenges. These include limitations on maximum adhesion strength imposed by microstructural dimensions, restricted adaptability to surfaces with varying degrees of roughness, and an inherent trade-off between adhesion strength and switchability. This review explores how shape memory polymers (SMPs) can address these challenges and, through their rubber-to-glass (R2G) transition capability, provide a powerful foundation for the next generation of smart dry adhesives. Specifically, we summarize and elucidate the mechanisms by which SMPs enhance adhesion strength and switchability through material characteristics such as tunable stiffness, shape-locking, and shape-memory effects. Additionally, we discuss a wide range of innovative designs and applications of SMP adhesives, offering insights into the ongoing challenges and emerging opportunities in this rapidly evolving field. [ABSTRACT FROM AUTHOR]

Semi‐interpenetrating polymer networks (SIPNs) have garnered significant interest due to their potential applications in self‐healing materials, drug delivery systems, electrolytes, functional membranes, smart gels and, toughing. SIPNs combine the characteristics of physical cross‐linking with advantageous chemical properties, offering broad application prospects in materials science and engineering. This perspective introduces the history of semi‐interpenetrating polymer networks and their diverse applications. Additionally, the ongoing challenges associated with traditional semi‐interpenetrating polymer materials are discussed and provide an outlook on future advancements in novel functional SIPNs. [ABSTRACT FROM AUTHOR]

Proximity sensing technology, which can obtain information without physical contact, has become an ideal choice in scenarios where physical contact is not feasible. Despite substantial advancements in tactile sensing, proximity sensing technology still holds great potential and has yet to be fully developed. Among numerous proximity sensing technologies, the fringing‐effect‐based capacitive proximity sensor (FE‐CPS) has garnered considerable attention due to its low cost, low power consumption, wide sensing range, and flexible and versatile structural design. However, research on FE‐CPS has not yet formed a complete system, and its development and intellectualization are still in their infancy, urgently requiring a systematic review to advance its development. This paper systematically summarizes the recent advances in FE‐CPS, from basic theory to practical applications. The working principle and typical structure of FE‐CPS are first introduced, followed by a discussion of methods for optimizing device performance. Furthermore, the application scenarios of FE‐CPS in intelligent pre‐alarm systems, intelligent control systems, and intelligent material perception systems are reviewed. Finally, the future development and challenges faced by FE‐CPS are prospected. [ABSTRACT FROM AUTHOR]

Elastic aerogels are ultra‐lightweight, highly porous materials widely used in fields such as sensing, aerospace, and thermal insulation. However, constrained by weak mechanical properties under deformation, the strength and elasticity of aerogels are mutually exclusive and difficult to reconcile. In this study, a triboelectric aerogel with a centripetal structure is constructed using a supramolecular system in combination with ice‐templating, resulting in outstanding mechanical properties (specific strength of 186.67 kN m kg−1) and rapid recovery speed (792 mm s−1). The key to reconciling strength and elasticity lies in multiscale structural synergy, mitigating local stress through controlled inelastic deformation to balance resistance and deformation. A portable triboelectric sensor is developed based on this material, offering motion protection and posture monitoring. This study addresses the challenge of reconciling elasticity and strength in aerogels, providing new insights for designing elastic smart materials. [ABSTRACT FROM AUTHOR]

Developing visible‐light‐driven fluorescent photoswitches in the solid state remains an enormous challenge in smart materials. Such photoswitches are obtained from salicylaldimines through excited‐state intramolecular proton transfer (ESIPT) and subsequent cis‐trans isomerization strategies. By incorporating a bulky naphthalimide fluorophore into a Schiff base, three photoswitches achieve dual‐mode changes (both in color and fluorescence) in the solid state. In particular, the optimal one generates triple fluorescence changing from green, to yellow and finally to orange upon visible‐light irradiation. This switching process is fully reversible and can be repeated at least 10 times without obvious attenuation, suggesting its good photo‐fatigue resistance. Mechanism studies reveal that the naphthalimide group not only enables the tuning of multicolor with an additional emission, but also induces a folded structure, reducing molecular stacking and facilitating ESIPT and cis‐trans isomerization. As such, photopatterning, ternary encoding and transient information recording and erasing are successfully developed. The present study provides a reliable strategy for visible‐light‐driven fluorescent photoswitches, showing implications for advanced information encryption materials. [ABSTRACT FROM AUTHOR]

Organic cocrystals, representing one type of new functional materials, have gathered significant interest in various engineering areas. Owing to their diverse stacking modes, rich intermolecular interactions and abundant functional components, the physicochemical properties of organic cocrystals can be tailored to meet different requirements and exhibit novel characteristics. The past few years have witnessed the rapid development of organic cocrystals in both fundamental characteristics and various applications. Beyond the typical properties like ambipolarity, emission tuning ability, ferroelectricity, etc. that are previously well demonstrated, many novel, impressive and cutting‐edge properties and applications of cocrystals are also emerged and advanced recently. Especially during the nearest five years, photothermal conversion, room‐temperature phosphorescence, thermally activated delay fluorescence, circularly polarized luminescence, organic solid‐state lasers, near‐infrared sensing, photocatalysis, batteries, and stimuli responses have been reported. In this review, these new properties are carefully summarized. Besides, some neoteric architecture and methodologies, such as host–guest structures and machine learning‐based screening, are introduced. Finally, the potential future developments and expectations for organic cocrystals are discussed for further investigations on multiple functions and applications. [ABSTRACT FROM AUTHOR]

Smart emulsions are both versatile additives to smart materials and functional smart materials themselves, acting as active components and structural elements driving innovative development. Emulsions offer versatility, ease of manipulation, and stability to smart materials. This review explores the multifaceted roles of emulsions, examining their formulation methods, applications, and role as building blocks in smart materials. The significance of emulsions in smart materials is discussed for applications such as drug delivery and adaptive coatings, as well as their role in stimuli‐responsive colloidal systems and nanocomposites. The smart emulsions reviewed encompass all manner of material types, including fluid and solid/polymerized smart materials. These include both emulsions with dynamic properties and emulsions used in the process of synthesizing other materials. Smart emulsions are categorized by application into shape memory, self‐healing, biological, and stimuli‐responsive, with analysis of formulation methods, metrics, and methods of final incorporation. Smart emulsions can be found initially as fluid systems and some react into solid polymers, tailored to meet functional needs. A comparative analysis reveals emerging trends such as coupling coating self‐healing/corrosion inhibition and use of waterborne polyurethanes. The discussion of smart emulsions concludes by outlining challenges and future directions for leveraging smart emulsions. [ABSTRACT FROM AUTHOR]

Novel earthquake‐resistant materials are of interest to the academic community because they have the potential to reduce seismic residual displacements and, by extension, maintenance costs. Smart materials and technologies have enhanced the seismic response of reinforced concrete (RC) buildings, but the effect of these advancements on issues that arise after earthquakes in RC‐coupled walls has not yet been investigated. This research scrutinizes the seismic performance of RC‐linked walls reinforced with NiTi, FeNCATB, and CuAlMn superelastic shape memory rebar in the boundary regions. As a part of the case study, three RC‐linked wall systems with four, eight, and twelve stories were adopted. The highest critical values for the inter‐story drift ratio (IDR) and the residual inter‐story drift ratio (RIDR) were obtained through the OpenSees program. According to the results, RIDR markedly reduces whenever concerns about the quake's aftermath are highlighted. In accordance with findings, among the whole adopted shape memory alloy (SMA) types in this research, the RC‐coupled wall based on Cu demonstrates superior results concerning RIDR and performs adequately regarding the restoring effect. As a result, seismically involved areas exposed to significant ground motions are typically recommended to use Cu‐based SMA material. [ABSTRACT FROM AUTHOR]

Thermochromic smart windows have attracted widespread attention in the field of solar modulation and building energy conservation. However, current materials of smart windows are still confronted with challenges, including low integrated luminous transmittance (Tlum), low solar energy modulation (ΔTsol), weak mechanical properties, and invariable critical transition temperature (τc). Herein, hydrophobic polyether side chains, that can reversibly undergo adjustable temperature‐triggered hydrophobic association, are introduced to thermochromic hydrogels for the first time. Due to the reversible phase separation, the obtained hydrogels demonstrate high Tlum (92.69%), high ΔTsol (82.15%), widely adjustable τc and fast transition rate (<4 s). Furthermore, the adjustable τc of hydrogel is independent of component changes, attributed to the rearrangement of physical‐crosslinked chain segments at various temperatures. Moreover, strong hydrogen bond and high entanglement endow the hydrogel with outstanding mechanical properties (tensile strength >0.45 MPa, elongation >440%). The results of simulation investigations in different cities illustrate that the hydrogels have excellent solar modulation and temperature regulation capabilities. Meanwhile, the thermochromic hydrogel possesses remarkable 3D‐printability and real‐time state monitoring capability, meeting the requirements of different climates and practical application. Therefore, the strategy proposed in this work provides innovative insights for thermochromic hydrogel smart windows and building energy conservation. [ABSTRACT FROM AUTHOR]

Magnetorheological elastomers (MREs), consisting of elastomers or thermoplastic elastomers (TPEs) as the soft matrix, are smart functional materials gaining attention in a wide variety of fields. TPEs offers several advantages such as easy processability and requirement of lesser additives, but their additive manufacturing using fused deposition modelling is challenging due to filament buckling and poor layer coalescence. Thus, this work presents the additive manufacturing of smart MREs consisting of spherical carbonyl iron powder (CIP) particles incorporated in styrene-ethylene-butylene-styrene (SEBS) block copolymer matrix using solvent-cast 4D (SC-4D) printing. The effect of varying filler amount on the physicomechanical and electrical characteristics of additively manufactured samples was investigated. Shore hardness and density of the MRE samples increased consistently with an increase in CIP content. However, density deviated significantly from the theoretical density beyond critical filler content (> 60 wt%). Tensile strength improved with CIP content up to 30 wt% and reduced on further increase in filler content. Elastic modulus predicted from six different theoretical models was compared with experimental results. The predictions deviated significantly from the experimental observations at higher filler contents due to complex particle–particle and particle–matrix interactions. Shrinkage and morphology analysis revealed that an increase in CIP content decreased the shrinkage and improved the shape stability of the samples. Electrical conductivity of the MRE samples was found to be close to neat SEBS sample below percolation threshold (~ 50 wt%). Beyond percolation threshold, electrical conductivity increased dramatically. Finally, the actuation capability of the flexible grippers was demonstrated in the presence of an external magnetic field. [ABSTRACT FROM AUTHOR]

Monolayer atomic crystals show significant advantages in improving charge storage kinetics for electrode materials. While notable progress is made, challenges remain in producing nanocrystals with desirable configurations, dimensions, and crystallographic properties. Here, 1D single‐crystal nanobelts assembled from monolayer sodium titanate nanobelts are reported with highly exposed active sites as anode materials for sodium‐ion batteries (SIBs). The unique structural properties of the 1D single‐crystal nanobelts offer excellent electrochemical activity, electrochemo‐mechanical stability, and well‐maintained structural integrity, leading to highly efficient sodium ion storage performance. Insights into the electrochemical reaction processes, as revealed by in situ transmission electron microscopy, in situ synchrotron X‐ray diffraction, and theoretical calculations, indicate that the 1D single‐crystal nanobelts enable favorable sodium ion storage kinetics and a low‐strain characteristic. This facilitates fast charge/discharge capability and long‐term cycling stability for up to 5000 cycles at 20 C. Moreover, the 1D single‐crystal nanobelts demonstrate practical applicability. A pouch cell assembled with the 1D single‐crystal nanobelts anode and iron‐based Prussian blue cathode exhibits highly stable cycling, achieving a low capacity fading ratio of ≈0.05% per cycle over 150 cycles. This study provides an innovative design principle to enhance the charge storage capability of electrode materials through intelligent structural nanoengineering. [ABSTRACT FROM AUTHOR]

Advanced optical information encryption usually relies on the integration of multicolor, stimulus‐responsive, and afterglow luminescence. However, achieving these simultaneously within a single‐phase system has posed challenges, complicating the design process. In this study, an advanced 3D information encryption strategy is presented based on undoped and alloyed Cs₂CdCl₄, encrypted through three distinct channels: emission wavelength, water stimulation, and afterglow time. Specifically, Mn2+, Sb3+, and Ag+ doped Cs₂CdCl₄ single crystals are successfully synthesized via a modified hydrothermal method, which exhibit bright orange, green, and blue emissions, respectively. Decryption of specific information can be achieved by employing corresponding narrowband filters. Furthermore, the Cs₂CdCl₄ system demonstrates hydrochromism, attributed to water‐induced sequential phase transitions. Upon water treatment, the 2D Cs₂CdCl₄ will undergo a phase transition to Cs3Cd2Cl7, and finally to cubic CsCdCl3. Interestingly, the resultant CsCdCl3 exhibits pronounced afterglow, originating from the triplet emission of Cd ions. Leveraging these unique properties, a highly secure and adjustable 3D encrypted quick response code is designed. The encrypted information is encoded in coordinates, and decrypted information can be retrieved in both compressed and decompressed modes as required. These findings pave the way for the development of novel smart photonic materials and multimodal optical information encryption. [ABSTRACT FROM AUTHOR]