Multifunctional Performance Research Articles

Transparent multifunctional cellulose-based conductive hydrogel for wearable strain sensors and arrays

Conductive hydrogels as promising candidate materials for flexible strain sensors have gained considerable attentions. However, it is still a great challenge to construct hydrogel with multifunctional performance via natural polymer. Herein, a novel multifunctional conductive hydrogel based on methylcellulose and cellulose nanocrystal was prepared via a facile and low-cost strategy. Methylcellulose (MC) was introduced to not only guarantee the stability of tannic acid coated cellulose nanocrystal (TA@CNCs) in LiCl solution, but also improve anti-freezing ability. The obtained hydrogel exhibited high transparency (98 % at 800 nm), good stretchability (663.1 %), low temperature tolerance (−23.9 °C), superior conductivity (2.89 S/m) and excellent UV shielding behavior. Flexible strain sensor assembled by the prepared hydrogels can be used to detect human body motions include subtle and large motions, and exhibited good sensitivity and stability over a wide temperature range. Multiple flexible hydrogels can also be assembled into a 3D sensor array to detect the distribution and magnitude of spatial pressure. Therefore, the hydrogels prepared via natural polymers will have broad application prospects in wearable devices, electronic skin and multifunctional sensor components.

Room temperature ammonia sensor with high selectivity based on the composite materials assembled by CuO nanosheets and WS2 nanoflakes

In this work, CuO nanosheets are synthesized by one-step hydrothermal method and CuO/WS2 heterostructures are fabricated by introducing CuO doping into WS2, the preparation method was employed to enhance the performance of the gas sensor. The CuO/WS2 heterostructure nanocomposite sensor, doped with 5 % CuO, exhibited a pronounced enhancement in its response to 30 ppm of ammonia gas at ambient temperature, increasing the response value from 3.8 observed in pure WS2-based sensors to 4.7. Specifically, the response time of the CuO/WS2 heterostructure-based gas sensor decreased to 180 s, whereas the WS2-based sensor required 350 s for NH3 detection at room temperature. Furthermore, the CuO/WS2 sensor demonstrated outstanding selectivity for ammonia, maintaining stability over a 90-day test with a response fluctuation of less than 5 %. The heterojunction formed by CuO and WS2 showed superior sensitivity to NH3 compared to pristine WS2, owing to a notable enhancement in the surface catalytic effect. It also displayed sensitivity to humidity, with a response value of 6.25 at a 71 % relative humidity. At last, the gas sensing and enhanced gas sensing performance mechanisms of the composites for NH3 were elucidated. This remarkable multi-functional performance offers valuable insights for the advancement of room temperature gas sensors with diverse sensing functionalities.

Large flakes of Al–Ti3C2Tx MXene constructing highly ordered layered MXene/ANF films with integrated multifunctionalities

The simultaneous realization of high mechanical properties and excellent multifunctional performance for nanocomposite films is still a key challenge for practical applications. In this work, a dilute MXene (Al–Ti3C2Tx)/aramid nanofiber (ANF) dispersion (0.013 wt%) containing large-sized, long-term stable Al–Ti3C2Tx nanosheets (5.58 ± 1.68 μm) and branched ANFs was filtered under vacuum pressure to obtain highly ordered layered Al–Ti3C2Tx/ANF nanocomposite films with different Al–Ti3C2Tx contents (orientation factor: 0.91). Among them, the 40 wt% Al–Ti3C2Tx/ANF film offers the benefits of excellent mechanical properties (strength: 200.79 ± 1.32 MPa, strain-to-failure: 8.05 ± 0.65 %, toughness: 9.96 ± 0.84 MJ/m3), high electrical conductivity (201.6 ± 5.5 S/cm), superior EMI shielding effectiveness of up to 15 264 dB cm2 g−1 in accordance with the theoretical calculation and high electrothermal conversion temperature up to ≈120.7 °C with a rapid response time of 4 s. In addition, the nanocomposite film also boasts a superhydrophobic property with a water contact angle of 162.0 ± 1.6° along with flame retardancy. The inherent properties of 2D materials and their highly ordered arrangement in the polymer matrix are expected to provide a feasible design proposal for preparing all-in-one multifunctional films.

Porous nickel sulfide nanorods serve as a multifunctional electrocatalyst for the hydrogen evolution reaction, urea electrooxidation reaction, and nitrate reduction reaction

The proposed hard-template-high-temperature calcination method effectively maintains the morphology of the template, and the prepared NiS electrocatalyst exhibits excellent multifunctional electrocatalytic performance.

Microcosmic modulation of the Co–N bonding structure improves the multi-functional electrocatalytic performance

The coordination environment of Co–Nx models is modulated in systematic theoretical studies. Thereinto, the well-defined Co-phenazine bonding structure (Co–N2) can efficiently reduce the reaction energy barrier for ORR and OER.

Modeling-driven materials by design for conjugated polymers: insights into optoelectronic, conformational, and thermomechanical properties.

Conjugated polymers (CPs) have emerged as pivotal functional materials in the realm of flexible electronics and optoelectronic devices due to their unique blend of mechanical flexibility, solution processability, and tunable optoelectronic properties. This review synthesizes the latest molecular simulation-driven insights obtained from various multiscale modeling techniques, including quantum mechanics (QM), all-atomistic (AA) molecular dynamics (MD), coarse-grained (CG) modeling, and machine learning (ML), to elucidate the optoelectronic, structural, and thermomechanical properties of CPs. By integrating findings from our recent computational work with key experimental studies, we highlight the molecular mechanisms influencing the multifunctional performance of CPs. This comprehensive understanding aims to guide future research directions and applications in the modeling assisted design of high-performance CP-based materials and devices.

3D porous cementitious electrolytes with “stream-reservoir” ionic channels for high multifunctional performance structural supercapacitors

Structural supercapacitors (SSCs) have attracted extensive attention due to load bearing/energy storage in zero energy buildings (ZEBs).

Multi-use of small performance halls – case studies of modern cultural facilities in Poland

Contemporary architecture is expected to meet not only functional goals and high aesthetic quality, but also to take into account changing social needs, which is in line with the trend towards sustainable building. It is therefore important to consider the idea of multifunctionality when implementing new developments, especially in small towns. The subject of this paper is the analysis of three buildings in Wieliczka, Dąbrowa and Pszczyna, in which the aspect of multifunctionality was considered differently. At the same time, the discussed examples will benefit researchers, investors and designers alike, as they present specific architectural aesthetic and technological solutions related to the realization of small auditoriums – a subject that is rarely dealt with in scientific publications. The main aim of this paper was to draw attention to the need for an individual approach to the design process and a multi-criteria search for optimal design solutions for the hall, moving away from standardization. Finally, the realization of small multifunctional performance space fits in with the idea of sustainable development, which is based on combining the needs of the present generation with the ability to meet the needs of future generations.

Study on the Microstructure and Properties of FeCoNiCrAl High-Entropy Alloy Coating Prepared by Laser Cladding-Remelting

Laser remelting technology effectively repairs defects such as pores and cracks in the coating. To investigate the impact of laser remelting on high-entropy alloy coatings, this study used Q235 steel as the substrate and employed laser cladding technology to prepare FeCoNiCrAl high-entropy alloy coatings, followed by laser remelting treatment. The phase composition and microstructure of the coatings were extensively characterized using equipment such as optical microscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). Additionally, the wear resistance and corrosion resistance of the coatings were tested using a multifunctional material surface performance tester, an electrochemical workstation, and SVET (Scanning Vibrating Electrode Technique). The results indicate that following laser remelting treatment, the atomic proportion of Fe elements on the coating surface decreased from 33.21% to 26.03%, while the atomic proportion of Al elements increased from 12.56% to 20.31%. The phase composition of the coating underwent a marked transformation, shifting from a structure composed of FCC, A2, and B2 phases to a singular BCC structure characterized by the presence of A2 and B2 phases. Concurrently, the grain morphology on the coating surface transitioned from elongated plate-like grains to equiaxed grains. Laser remelting enhanced the wear resistance of the coating. Laser remelting had no significant impact on the corrosion resistance of the non-cracked regions of the coating.

Tunable Multifunctional Metamaterial Sandwich Panel with Quasi‐Zero Stiffness Lattice Cores: Load‐Bearing, Energy Absorption, and Vibration Isolation

AbstractThe interest in novel mechanical metamaterials that offer advanced functionalities and mechanical tunability for highly compatible multifunctional performance in state‐of‐the‐art engineering applications is growing. Here, a novel tunable multifunctional mechanical metamaterial, also known as a metamaterial sandwich panel, which can achieve load‐bearing, energy absorption, and low‐frequency vibration isolation properties simultaneously, is reported. The designed metamaterial sandwich panel is composed of a quasi‐zero stiffness (QZS) lattice core and two kirigami‐style surfaces, which endow the metamaterial sandwich panel with multi‐function performance and tunable properties. As a proof‐of‐concept, the mechanical properties and tunable multifunctional performance of the proposed metamaterial sandwich panel are demonstrated both in simulations and experiments. This work provides a new alternative for designing novel mechanical metamaterials with tunable multifunctional performance and may have potential applications in a variety of engineering applications, such as medical transportation, marine systems, and aerospace applications.

Smart Composite Coatings for Corrosion Protection

Corrosion is a major problem faced by the automobile industry. To overcome corrosion, the industry relies on surface coatings in which metallic (Zn, Cr etc.) and polymeric coatings (polyurethane, epoxy, etc.) are widely recommended. However, currently smart, self-healing coatings are considered to be the state of the art option to inhibit cut-edge corrosion and to enhance the life-time. The direct introduction of inhibitors into any matrix creates undesirable effects, majorly the integrity of the inhibitor with the matrix and spontaneous release. Hence, loading inhibitors into a suitable container and subsequent release of the same when the coating is damaged favors the self-healing property of a coating, which results in high durability.Such a smart coating can be achieved by the synthesis of porous silica particles, which can be an effective corrosion inhibitor container. They possess exceptional properties like nontoxicity, high surface area, and capability to be filled with different types of active materials, including organic, inorganic, and hybrid inhibitors. Hence, these can be the equivalent and non-toxic alternative to chromates which are toxic and carcinogenic to the environment and the living system.Among the different porous containers reported in the literature, mesoporous silica nanoparticles have large surface area which is beneficial to load the required quantity of corrosion inhibitors. The corrosion inhibitor-loaded porous silica containers are compatible with different matrices, including metals, polymers, and ceramics, to prepare the composite materials. To control the instant release of the loaded inhibitors, encapsulation with a polyelectrolyte is required. As a result, improved self-healing properties can be achieved as compared to the particles without encapsulation.Among the various types of porous silica, Santa Barbara Amorphous-15 (SBA-15) has several benefits, including the ease of preparation, nontoxic precursors, hexagonal structure to carry a high quantity of material, size range from micro to nanometer, controllable pore size (20-500Å), large specific surface area (∼1000m2/g), porosity, surface morphology and huge pore volume. This work describes the synthesis of mesoporous silica (SBA-15) using a three-step solvo-thermal process. The process includes template preparation (synthesis of mesoporous silica), loading with benzotriazole (BTA) an organic corrosion inhibitor, followed by Poly(diallyldimethylammonium chloride) (PDDA) encapsulation.The synthesised mesoporous silica was characterised for morphological features, porosity, and surface charge. Based on the BET analysis, successful modification of the mesoporous silica particles at different stages shows a reduction in the surface area and pore volume. The zeta (ζ)-potential measurements showed a significant variation in surface charge after the modification of the mesoporous silica particles. The releasing nature of BTA before and after the PDDA encapsulation was studied using UV-Visible technique at different pH levels. Based on the characterisation of the PDDA encapsulated inhibitor-loaded mesoporous silica particles, appropriate coating was prepared by incorporating these particles into eg. metallic (Zn coating) and/or polymeric (epoxy coating) matrices. The release and corrosion inhibition performance of these coatings were studied using electrochemical techniques. The multi-functional performance of these coatings would be highlighted.

Gradient honeycomb metastructure with broadband microwave absorption and effective mechanical resistance

Multifunctional metastructure integrated broadband microwave absorption and effective mechanical resistance has attracted much attention. However, multifunctional performance is limited by the lack of theoretical approaches to integrated design. Herein, a multi-layer impedance gradient honeycomb (MIGH) was designed through theoretical analysis and simulation calculation, and fabricated using 3D printing technique. A theoretical calculation strategy for impedance gradient structure was established based on the electromagnetic parameter equivalent method and the multi-layer finite iterative method. The impedance of MIGH was analyzed by the theoretical calculation strategy to resolve the broadband absorption. Intrinsic loss mechanism of matrix materials and distributions of electric fields, magnetic fields and power loss were analyzed to investigate the absorption mechanism. Experimental results indicated that a 15 ​mm thick designed metastructure can achieve the absorption more than 88.9% in the frequency range of 2-18 ​GHz. Moreover, equivalent mechanical parameters of MIGH was calculated by integral method according to the Y-shaped model. Finite Element analysis of stress distributions were carried out to predict the deformation behavior. Mechanical tests demonstrate that MIGH achieved the compression modulus of 22.89 ​MPa and flexure modulus of 17.05 ​MPa. The integration of broadband electromagnetic absorption and effective mechanical resistance was achieved by the proposed design principle and fabrication methodology.

The multifunctional performance of the laser powder bed fusion 316L stainless steel matrix composite reinforced with the CNT-ZrO2 nanohybrid

The effects of CNT-ZrO2 nanohybrid reinforcement on the microstructure features, mechanical properties, wear behavior, and corrosion resistance of laser powder bed fusion (LPBF) stainless steel 316L (SS 316L) were analyzed. X-ray diffraction, scanning electron microscopy, Raman analysis, tensile, pin-on-disk, and potentiodynamic polarization tests were conducted to determine the function of the CNT-ZrO2 nanohybrid reinforcement in enhancing the properties of the fabricated LPBF SS 316L matrix composite. The hardness, tensile properties, wear behavior, and corrosion resistance of the LPBF composites with various wt.% of the CNT-ZrO2 nanohybrid were compared with those of the unreinforced SS 316L and the SS 316L matrix composite containing detached CNTs and ZrO2 nanoparticles. The outcomes demonstrated a synergistic influence between the CNT and ZrO2 in an integrated nanosystem in improvement in the hardness, strength, wear behavior, and corrosion resistance of prepared composites.

Biomimetic Antibacterial Gelatin Hydrogels with Multifunctional Properties for Biomedical Applications.

A facile novel approach of introducing dopamine and [2-(methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide via dopamine-triggered in situ synthesis into gelatin hydrogels in the presence of ZnSO4 is presented in this study. Remarkably, the resulting hydrogels showed 99.99 and 100% antibacterial efficiency against Gram-positive and Gram-negative bacteria, respectively, making them the highest performing surfaces in their class. Furthermore, the hydrogels showed adhesive properties, self-healing ability, antifreeze properties, electrical conductivity, fatigue resistance, and mechanical stability from -100 to 80 °C. The added multifunctional performance overcomes several disadvantages of gelatin-based hydrogels such as poor mechanical properties and limited thermostability. Overall, the newly developed hydrogels show significant potential for numerous biomedical applications, such as wearable monitoring sensors and antibacterial coatings.

Beyond honeycombs: Core topology's role in 3D-printed sandwich panels

Innovative sandwich structures have gained prominence due to their potential to revolutionize industries with multifunctional performance. This study investigates the impact of different core topologies on the energy absorption capability of 3D-printed sandwich panels. Triply periodic minimal surfaces-based lattice structures and bioinspired spherical closed-cell foam structures were designed and compared against a traditional honeycomb structure to find the most suitable core topology. The fused deposition modeling technique was used to print samples in polylactic acid. The mechanical behavior of the 3D printing material was comprehensively characterized through a uniaxial tensile test. The sandwich panels were subjected to low-velocity impact loads to determine the dependence of their mechanical properties’ responses on their topological features. Deformation mechanisms were investigated experimentally and numerically using ANSYS. The impact of cellular core topologies on deformation mechanisms, multi-hit (and impact location), and energy absorption capabilities demonstrated the possibility of enhancing mechanical performance of the panels. It is found that the sandwich panels with Tetra Radial and Schwarz P core topologies exhibit higher performance, denoted by higher dynamic energy absorption (up to 11% and 16%, respectively, for the 1st impact) and stiffness (up to 42%, and 43%, respectively, for the 1st impact) than the honeycomb structure (with a constant relative density). Significant enhancements in energy absorption, particularly in Schwarz P and Mono Radial panels compared to the previously reported Octet core structure, offer valuable insights for lightweight, durable 3D-printed sandwich structures, with broad applications in multifunctional industries and future trends in materials engineering, promising applications in aerospace, automotive, and construction for the development of weight-efficient, structurally robust materials.

Developing a class of dual atom materials for multifunctional catalytic reactions

Dual atom catalysts, bridging single atom and metal/alloy nanoparticle catalysts, offer more opportunities to enhance the kinetics and multifunctional performance of oxygen reduction/evolution and hydrogen evolution reactions. However, the rational design of efficient multifunctional dual atom catalysts remains a blind area and is challenging. In this study, we achieved controllable regulation from Co nanoparticles to CoN4 single atoms to Co2N5 dual atoms using an atomization and sintering strategy via an N-stripping and thermal-migrating process. More importantly, this strategy could be extended to the fabrication of 22 distinct dual atom catalysts. In particular, the Co2N5 dual atom with tailored spin states could achieve ideally balanced adsorption/desorption of intermediates, thus realizing superior multifunctional activity. In addition, it endows Zn-air batteries with long-term stability for 800 h, allows water splitting to continuously operate for 1000 h, and can enable solar-powered water splitting systems with uninterrupted large-scale hydrogen production throughout day and night. This universal and scalable strategy provides opportunities for the controlled design of efficient multifunctional dual atom catalysts in energy conversion technologies.

Solid state reaction preparation of BaMg2Si4O10F2:Eu3+ synthetic-mica phosphor for latent fingerprint identification

Synthetic-mica materials have shown multifunctional performances due to their distinctive adhesion and cation exchange ability. In this work, a novel Eu3+-doped synthetic-mica named as barium tetrasilicate fluorphlogopite (BaMg2Si4O10F2) phosphor was prepared by the high-temperature solid state reaction process for the first time. The as-prepared mica samples possess a distinct lamellar structure, as indexed by X-ray diffraction, scanning and transmission electron microscopy means. The photoluminescence results manifest that the phosphor can generate bright red emission at 614 nm corresponding to the characteristic 5D0→7F2 transition of Eu3+ as excited with UV light, and the luminescence intensity is nearly 9-fold in comparison with that in original fluorphlogopite. The more fantastic result is that the emission intensity at 373 K still retains 95 % in respect to that at ambient temperature, demonstrating the phosphor system with excellent optical thermal stability. The optimal BaMg2Si4O10F2:8%Eu3+ phosphor powder has been used to discern the latent fingerprints on the surface of diverse non-porous and semi-porous substrates, which reveal the superior visibility as irradiated with 254 nm UV light. The Eu3+-doped BaMg2Si4O10F2 synthetic-mica is a promising phosphor material for latent fingerprint identification application.

Time-division based integrated sensing, communication, and computing in integrated satellite-terrestrial networks

In this paper, we investigate time-division based framework for integrated sensing, communication, and computing in integrated satellite-terrestrial networks. We consider a scenario, where Internet-of-Things devices on the ground operate with sensing and communication in a time-division manner, and can process the sensing results locally, at the edge, or in the cloud via the satellite communication link. Based on the proposed framework, we formulate a multi-dimensional optimization problem to maximize the utility performance of sensing, communication, and computing abilities. After decomposing the original optimization problem into two subproblems, we first derive the closed-form solution of the optimal task partitioning strategy for terrestrial users and satellite users. Then, we develop the joint subframe allocation and task partitioning strategy to optimize the overall performance, by means of which the Pareto optimal solutions can be obtained along the Pareto frontier. Extensive simulations are provided to demonstrate the effectiveness of the proposed strategy, which is 10% to 60% superior compared with the benchmarks. Also, the trade-off between the multidimensional resource and multi-functional performance is analyzed from the perspective of network design.

Interface engineering of carbon fiber composites using CNT: A review

AbstractThis paper aims to explore the potential of carbon nanotubes (CNTs) in enhancing the structural capability and multifunctionality of carbon fiber composites in aerospace applications, primarily by focusing on interfacial applications. The conventional method of dispersing CNTs in a matrix is not fully efficient in exploiting the mechanical and multifunctional performance of CNTs. Hence, the use of CNTs at the interface or as a coating on the surface of carbon fibers has been suggested as a means of achieving multifunctionality, in addition to enhanced mechanical performance. The paper presents an overview of the various processes for growing CNTs on carbon fiber surfaces and examines the effects of CNT geometry and growth parameters on the properties of grafted fibers and their composites. Furthermore, it discusses the potential improvements in thermal and electrical conductivity achievable by incorporating CNTs at the interface, as well as the benefits of using CNTs as a sizing layer for carbon fibers, including enhanced fracture toughness and resistance to delamination.Highlights Comprehensive study of interface engineering in carbon fibers and Carbon Fibre Reinforced Plastic (CFRPs) using carbon nanotubes (CNTs). Improved transverse mechanical properties and overall thermal and electrical properties. Multifunctional applications possible with the use of CNT. Both experimental and numerical studies reviewed.

Exploring internal structures and properties of terpolymer fibers via real-space characterizations.

While significant research has investigated the processing and properties of high-performance terpolymer fibers, much remains to be understood about the internal nano- and microstructures of these fibers, and how these morphologies relate to fiber properties. Here we use a focused ion beam notch technique and multifrequency atomic force microscope mapping to characterize the internal structure and local mechanical properties within Technora® fibers. We find a highly fibrillated structure that appears to connect with both the fiber's molecular chemistry and full-fiber mechanical properties. In addition, through detailed comparisons with Kevlar® K29 fibers, we find remarkable differences between the internal structures of the two fibers, and posit connections between our measurements and multifunctional performance studies from the literature.