Showing papers on "Smart material published in 2020"
TL;DR: The means by which aligned porous structures and nacre mimetic materials obtainable through recently developed freeze-casting techniques and low-dimensional building blocks can facilitate material functionality across multiple fields of application, including energy storage and conversion, environmental remediation, thermal management, and smart materials, are discussed.
Abstract: Freeze casting, also known as ice templating, is a particularly versatile technique that has been applied extensively for the fabrication of well-controlled biomimetic porous materials based on ceramics, metals, polymers, biomacromolecules, and carbon nanomaterials, endowing them with novel properties and broadening their applicability. The principles of different directional freeze-casting processes are described and the relationships between processing and structure are examined. Recent progress in freeze-casting assisted assembly of low dimensional building blocks, including graphene and carbon nanotubes, into tailored micro- and macrostructures is then summarized. Emerging trends relating to novel materials as building blocks and novel freeze-cast geometries-beads, fibers, films, complex macrostructures, and nacre-mimetic composites-are presented. Thereafter, the means by which aligned porous structures and nacre mimetic materials obtainable through recently developed freeze-casting techniques and low-dimensional building blocks can facilitate material functionality across multiple fields of application, including energy storage and conversion, environmental remediation, thermal management, and smart materials, are discussed.
307 citations
TL;DR: Hydrogels and shape memory polymers (SMPs) possess excellent and interesting properties that may be harnessed for future applications, but this is not achievable if their mechanical behaviors are uncontrolled.
Abstract: Hydrogels and shape memory polymers (SMPs) possess excellent and interesting properties that may be harnessed for future applications. However, this is not achievable if their mechanical behaviors ...
155 citations
TL;DR: Magnetorheological elastomers (MREs) are a class of recently emerged smart materials whose moduli are largely influenced when exposed to an external magnetic field as mentioned in this paper.
Abstract: Magnetorheological elastomers (MREs) are a class of recently emerged smart materials whose moduli are largely influenced when exposed to an external magnetic field. The MREs are particulate composites, where micro-sized magnetic particles are dispersed inside a non-magnetic polymeric matrix. These elastomers are known for changing their mechanical and rheological properties in the presence of a magnetic field. This change in properties is widely known as the magnetorheological (MR) effect. The MR effect depends on a number of factors such as type of matrix materials, type, concentration and distribution of magnetic particles, use of additives, working modes, and magnetic field strength. The investigation of MREs’ mechanical properties in both off-field and on-field (i.e. absence and presence of a magnetic field) is crucial to deploy them in real engineering applications. The common magneto-mechanical characterization experiments of MREs include static and dynamic compression, tensile, and shear tests in both off-field and on-field. This review article aims to provide a comprehensive overview of the magneto-mechanical characterizations of MREs along with brief coverage of the MRE materials and their fabrication methods.
150 citations
TL;DR: Because some molecular machines can function as molecular motors-which are capable of cycling a unidirectional motion out of thermodynamic equilibrium and progressively increasing the work delivered to their environment-one can expect unique opportunities to design new kinds of mechanically active materials and devices capable of autonomous behavior when supplied by an external source of energy.
Abstract: Artificial molecular machines are able to produce and exploit precise nanoscale actuations in response to chemical or physical triggers. Recent scientific efforts have been devoted to the integration, orientation, and interfacing of large assemblies of molecular machines in order to harness their collective actuations at larger length scale and up to the generation of macroscopic motions. Making use of such "hierarchical mechanics" represents a fundamentally new approach for the conception of stimuli-responsive materials. Furthermore, because some molecular machines can function as molecular motors-which are capable of cycling a unidirectional motion out of thermodynamic equilibrium and progressively increasing the work delivered to their environment-one can expect unique opportunities to design new kinds of mechanically active materials and devices capable of autonomous behavior when supplied by an external source of energy. Recently reported achievements are summarized, including the integration of molecular machines at surfaces and interfaces, in 3D self-assembled materials, as well as in liquid crystals and polymer materials. Their detailed functioning principles as well as their functional properties are discussed along with their potential applications in various domains such as sensing, drug delivery, electronics, optics, plasmonics, and mechanics.
131 citations
TL;DR: In this paper, the main processing and chemical synthesis routes available for the fabrication of lignin-based smart materials, and focus on their use as sensors, biomedical systems, and shape-programmable materials.
Abstract: Biomass-derived materials are green alternatives to synthetic plastics and other fossil-based materials Lignin, an aromatic plant polymer, is one of the most appealing renewable material precursors for smart materials capable of responding to different stimuli Here we review lignin-based smart materials, a research field that has seen a rapid growth during the last five years We describe the main processing and chemical synthesis routes available for the fabrication of lignin-based smart materials, and focus on their use as sensors, biomedical systems, and shape-programmable materials In addition to benchmarking their performance to the state of the art fossil counterparts, we identify challenges and future opportunities for the development of lignin-based smart materials towards new high-performance applications
110 citations
TL;DR: In this article, a review of 4D printing of smart systems and their applications in sensors, actuators and biomedical devices were reviewed to provide a deeper understanding of the current development and the future outlook.
101 citations
TL;DR: In this article, a comprehensive review of smart electrospun fibers for textile applications is presented, where the definition of smart fibers and the differences between interactive fibers and passive interactive fibers are briefly introduced.
100 citations
TL;DR: This review initially discusses a brief summary of the aforementioned stimuli-responsive smart materials following a complete description of some of the smart materials.
95 citations
TL;DR: The research carried out in the past five years, in the areas of modeling, and optimal positioning of piezoelectric actuators/sensors, for active vibration control, are covered.
Abstract: Considering the number of applications, and the quantity of research conducted over the past few decades, it wouldn't be an overstatement to label the piezoelectric materials as the cream of the crop of the smart materials. Among the various smart materials, the piezoelectric materials have emerged as the most researched material for practical applications. They owe it to a few key factors like low cost, large frequency bandwidth of operation, availability in many forms, and the simplicity offered in handling and implementation. For piezoelectric materials, from an application standpoint, the area of active control of vibration, noise, and flow, stands, alongside energy harvesting, as the most researched field. Over the past three decades, several authors have used piezoelectric materials as sensors and actuators, to (i) actively control structural vibrations, noise and aeroelastic flutter, (ii) actively reduce buffeting, and (iii) regulate the separation of flows. These studies are spread over several engineering disciplines-starting from large space structures, to civil structures, to helicopters and airplanes, to computer hard disk drives. This review is an attempt to concise the progress made in all these fields by exclusively highlighting the application of the piezoelectric material. The research carried out in the past five years, in the areas of modeling, and optimal positioning of piezoelectric actuators/sensors, for active vibration control, are covered. Along with this, investigations into different control algorithms, for the piezoelectric based active vibration control, are also reviewed. Studies reporting the use of piezoelectric modal filtering and self sensing actuators, for active vibration control, are also surveyed. Additionally, research on semi-active vibration control techniques like the synchronized switched damping (on elements like resistor, inductor, voltage source, negative capacitor) has also been covered
93 citations
TL;DR: A thorough search of the literature was carried out through SciFinder, ScienceDirect, SpringerLink, Wiley Online Library and reputed and peer-reviewed journals and a review was written as discussed by the authors.
Abstract: Smart materials also called intelligent materials are gaining importance continuously in many industries including aerospace one. It is because of the unique features of these materials such as self-sensing, self-adaptability, memory capabilities and manifold functions. For a long time, there is no review of smart materials. Therefore, it is considered worthwhile to write a review on this subject.,A thorough search of the literature was carried out through SciFinder, ScienceDirect, SpringerLink, Wiley Online Library and reputed and peer-reviewed journals. The literature was critically analyzed and a review was written.,This study describes the advances in smart materials concerning their applications in aerospace industries. The classification, working principle and recent developments (nano-smart materials) of smart materials are discussed. Besides, the future perspectives of these materials are also highlighted. Much research has not been done in this area, which needs more extensive study.,Certainly, this study will be highly useful for academicians, researchers and technocrats working in aerospace industries.
90 citations
26 Aug 2020
TL;DR: A simple approach to fabricate tensegrity structures made of smart materials using 3D printing combined with sacrificial molding that can pave the way toward more algorithmic designs of 3D soft machines.
Abstract: Tensegrity structures provide both structural integrity and flexibility through the combination of stiff struts and a network of flexible tendons. These structures exhibit useful properties: high stiffness-to-mass ratio, controllability, reliability, structural flexibility, and large deployment. The integration of smart materials into tensegrity structures would provide additional functionality and may improve existing properties. However, manufacturing approaches that generate multimaterial parts with intricate three-dimensional (3D) shapes suitable for such tensegrities are rare. Furthermore, the structural complexity of tensegrity systems fabricated through conventional means is generally limited because these systems often require manual assembly. Here, we report a simple approach to fabricate tensegrity structures made of smart materials using 3D printing combined with sacrificial molding. Tensegrity structures consisting of monolithic tendon networks based on smart materials supported by struts could be realized without an additional post-assembly process using our approach. By printing tensegrity with coordinated soft and stiff elements, we could use design parameters (such as geometry, topology, density, coordination number, and complexity) to program system-level mechanics in a soft structure. Last, we demonstrated a tensegrity robot capable of walking in any direction and several tensegrity actuators by leveraging smart tendons with magnetic functionality and the programmed mechanics of tensegrity structures. The physical realization of complex tensegrity metamaterials with programmable mechanical components can pave the way toward more algorithmic designs of 3D soft machines.
TL;DR: Recent advancements in 4D printing are discussed, focusing on smart polymers and cognate stimuli response, the compatibility of the material with the 3D printer, applications, and trends of 4D Printing of SMP.
TL;DR: A new soft magnetic composite material capable of reprogramming its magnetization profile without changing intrinsic magnetic properties of embedded magnetic particles or the molecular property of base material is reported.
Abstract: Soft magnetic materials have shown promise in diverse applications due to their fast response, remote actuation, and large penetration range for various conditions. Herein, a new soft magnetic comp...
TL;DR: Smart materials as controlled drug release vehicles for tissue engineering are described, highlighting their potential for the delivery of precise quantities of drugs at specific locations and times promoting the controlled repair or remodeling of tissues.
Abstract: Smart or stimuli-responsive materials are an emerging class of materials used for tissue engineering and drug delivery A variety of stimuli (including temperature, pH, redox-state, light, and magnet fields) are being investigated for their potential to change a material’s properties, interactions, structure, and/or dimensions The specificity of stimuli response, and ability to respond to endogenous cues inherently present in living systems provide possibilities to develop novel tissue engineering and drug delivery strategies (for example materials composed of stimuli responsive polymers that self-assemble or undergo phase transitions or morphology transformations) Herein, smart materials as controlled drug release vehicles for tissue engineering are described, highlighting their potential for the delivery of precise quantities of drugs at specific locations and times promoting the controlled repair or remodeling of tissues
01 Jan 2020
TL;DR: Insight is given to the state-of-the-art micro/nano-systems that are proposed for implantable and wearable diagnostic, therapeutic and treatment applications and their integration with various types of energy harvesters that makes the whole system self-sustained or battery-free.
Abstract: Smart materials offer a significant role in on our lives covering various sensing and actuation applications in healthcare due to their responsivity to external stimuli such as stress, light, temperature, moisture or pH, and electric or magnetic fields. These materials are also suitable for harvesting biomechanical energies from human motions, environment or body heat, or shaping of biofuel powered devices. This will open up the horizon for nanoenergy nanosystems that can themselves act as self-powered sensors or be utilized as power sources for other integrated transducers. This paper, gives an insight to the state-of-the-art micro/nano-systems that are proposed for implantable and wearable diagnostic, therapeutic and treatment applications. The unique property of these systems apart from the flexibility or conformability of the transducers (i.e. sensors and actuators) and the uniqueness of their building materials, is their integration with various types of energy harvesters that makes the whole system self-sustained or battery-free. The incorporation of these self-sustained systems into information technology affecting smart healthcare in significant ways.
TL;DR: In this article, a task-oriented entire landscape of 4D printing followed by a comprehensive smart material perspective is presented in this review, and the potential applications of 3D printing are summarised with promising research directions and outlook.
Abstract: Development in additive manufacturing is exceptionally rapid than the expected forecast so far and it has traced out new dimensions in engineering applications. 3D printing technology becomes more glamorous when Skylar Tibbits incorporated the concept of “Time” as a fourth dimension by encapsulating smart materials in current additive manufacturing technique. Materials having an explicit response to external stimuli over a certain time span are designated as smart materials and additive manufacturing of such time-dependent, programmable, and intelligent materials is termed as 4D printing. In 4D printing, primary 3D printed configuration switched exclusively into a transformed shape when exposed to an external stimuli, e.g. heat, light, water, chemical, electric current, magnetic field or pH. Perhaps, additive manufacturing technology seems to be superseded exclusively by this modern technology in forthcoming years, and much effort is demanding from every discipline to actualize this technology. A task-oriented entire landscape of 4D printing followed by a comprehensive smart material perspective is presented in this review. Graphical abstract set forth a route to the complete process comprehension. Moreover, other components of 4D technology like customary techniques, computational challenges, reversibility and current stature of 4D printing are probed through recent experimental and theoretical literature. Finally, potential applications of 4D printing are summarised with promising research directions and outlook. 4D printing: A future insight in additive manufacturing.
TL;DR: In this article, the authors define molecular switching chromic compounds as molecular systems which can reversibly change their molecular structures in response to one or more external stimuli, such as irradiation, magnetic or electric field, chemicals or gases, light, heat, mechanical effects or changes in pH.
TL;DR: A simple but versatile aggregation-induced emission luminogen that was sensitive to an electric stimulus and displayed reversibly three-color switched electrochromism and on-to-off electroluminochromism, which may offer an important guideline for multifunctional molecular design and provide an important step forward to expand the real-life applications of smart materials.
Abstract: There is still an urgent demand for novel smart materials that can achieve a diverse range of practical applications in the synthetic material area. Herein, we developed a simple but versatile aggregation-induced emission luminogen (AIEgen, 1). Compound 1 was sensitive to an electric stimulus and displayed reversibly three-color switched electrochromism and on-to-off electroluminochromism. Such properties allowed the fabrication of high-performance non-doped OLEDs with a high external quantum efficiency of 5.22%. Due to its AIE property and remarkable sensitive color change in response to polarity change, it can serve as a unique imaging probe for detecting environmental polarity in cells and selective visualization of lipid droplets in live tissues. More impressively, compound 1 exhibited a wide range of thermoresponsive behaviors with a ratiometric luminescence change and noticeable fluorescence color switching. As another remarkable feature, it can respond to anisotropic shearing force and isotropic hydrostatic pressure with prominent and contrasting luminescence conversion due to the distinct disturbance of the weak intermolecular interactions and charge transfer process. The present results may offer an important guideline for multifunctional molecular design and provide an important step forward to expand the real-life applications of smart materials.
TL;DR: The superior flexibility of freestanding single-crystalline BiFeO3 membranes is demonstrated, which are typical multiferroic materials with multifunctionality, which mainly originates from reversible rhombohedral-tetragonal phase transition, as revealed by phase-field simulations.
Abstract: The integration of ferroic oxide thin films into advanced flexible electronics will bring multifunctionality beyond organic and metallic materials. However, it is challenging to achieve high flexibility in single-crystalline ferroic oxides that is considerable to organic or metallic materials. Here, we demonstrate the superior flexibility of freestanding single-crystalline BiFeO3 membranes, which are typical multiferroic materials with multifunctionality. They can endure cyclic 180° folding and have good recoverability, with the maximum bending strain up to 5.42% during in situ bending under scanning electron microscopy, far beyond their bulk counterparts. Such superior elasticity mainly originates from reversible rhombohedral-tetragonal phase transition, as revealed by phase-field simulations. This study suggests a general fundamental mechanism for a variety of ferroic oxides to achieve high flexibility and to work as smart materials in flexible electronics.
TL;DR: In this paper, a review of the applications of Ga-based liquid metals and their hybrids is presented, focusing on their field-responsive physical and chemical properties and the types of field applied in each case.
TL;DR: This work aims to systematically describe the significant effect of magnetic fields on the functionality of the hydrogel, and introduces magnetic-field-induced assembly of nanomaterials with different dimensions and resulting functional performance.
Abstract: Hydrogels are composed of 3D hydrophilic networks with an abundance of water; they are analogous to biological soft tissues. Their unique physico-chemical properties endow hydrogels with great potential in many fields, including tissue engineering and flexible sensing. However, inadequate functionality, such as lack of rapid responsiveness, severely limits practical applications in many areas. Therefore, imparting functionality to the hydrogel is a hot research topic. The magnetic field, as an important physical field, provides a new strategy with a variety of advantages. Magnetic-field-induced ordered nano-assembly brought anisotropic properties and novel performance. Furthermore, the magnetic responsiveness of hydrogels with magnetic nanoparticles can lead to the generation of functionality under magnetic fields. Thus, we aim to systematically describe the significant effect of magnetic fields on the functionality of the hydrogel. In this review, magnetic-field-induced assembly of nanomaterials with different dimensions and resulting functional performance are introduced. The functionalities of hydrogels based on magnetic-field-induced macroscopic responses are also summarized. We believe this review will motivate more exploration of the application of magnetic fields to develop functional hydrogel materials.
TL;DR: A design rulebook for tetra-ortho-chloroazobenzenes, an emerging class of visible-light-responsive photochromes, by elucidating the role that substituents play in defining their key characteristics is presented in this paper.
Abstract: Molecular photoswitches enable reversible external control of biological systems, nanomachines, and smart materials. Their development is driven by the need for low energy (green-red-NIR) light switching, to allow non-invasive operation with deep tissue penetration. The lack of clear design principles for the adaptation and optimization of such systems limits further applications. Here we provide a design rulebook for tetra-ortho-chloroazobenzenes, an emerging class of visible-light-responsive photochromes, by elucidating the role that substituents play in defining their key characteristics: absorption spectra, band overlap, photoswitching efficiencies, and half-lives of the unstable cis isomers. This is achieved through joint photochemical and theoretical analyses of a representative library of molecules featuring substituents of varying electronic nature. A set of guidelines is presented that enables tuning of properties to the desired application through informed photochrome engineering.
TL;DR: The aim of this study is to define the features that smart buildings should fulfil in order to be compatible with the overall context of the smart city and to introduce a new evaluation framework of Smart Buildings Integration into a Smart City (SBISC).
Abstract: The aim of this study is to define the features that smart buildings should fulfil in order to be compatible with the overall context of the smart city and to introduce a new evaluation framework of Smart Buildings Integration into a Smart City (SBISC). By analysing scientific literature as well as existing international and local project examples, the features of smart buildings that are expected to be adopted in smart cities were identified. The SBISC evaluation methodology was developed and applied to a set of selected projects. The literature review revealed that the smart building and smart city concepts were developed in different time frames and by different stakeholders and, thus, need to be realigned. The most important aspect is to employ in a smart building all the functionalities proposed by the smart areas of the city and vice versa by enabling the recommended features of smart materials, smart building services, and smart construction to serve for the surrounding systems. Nine office buildings representing smart building concept in different smart cities built within the period 2007–2018 with a total area from 10,000 m2 to 143,000 m2 were selected for the analysis. The research of selected projects revealed that the smart buildings have more potential to become smarter by utilizing smart cities capabilities in the areas of smart energy, smart mobility, smart life, and smart environment. Smart cities are the most prominent trend in creating a cohesive environment.
TL;DR: Overall, it is believed that molecular martensitic materials are emerging as the next generation smart materials that have shown promise in advancing a wide range of domains of applications.
Abstract: Molecular martensitic materials are an emerging class of smart materials with enormous tunability in physicochemical properties, attributed to the tailored molecular and crystal structures through molecular design. This class of materials exhibits ultrafast and reversible structural transitions in response to thermal and mechanical stimuli, which underlies fascinating properties such as thermoelasticity, superelasticity, ferroelasticity, and shape memory effect. These dynamic properties are not widely explored in molecular crystals and therefore molecular martensitic materials represent a new frontier in the field of solid-state chemistry. In martensitic transitions, the materials not only exhibit substantial shape changes but also remember the functions in the associated polymorphic phases. This suggests promising applicability towards light-weight actuators, lifts, dampers, sensors, shape-/function-memory and ultraflexible optoelectronic devices. In this article, we review characteristics, detailed transition mechanisms, and potential applications of molecular martensitic materials. In particular, we aim to describe transition characteristics by collecting cases with similar transition principles in order to glean insights into further advancement of molecular martensitic materials. Overall, we believe that molecular martensitic materials are emerging as the next generation smart materials that have shown promise in advancing a wide range of domains of applications.
TL;DR: This paper consists of using smart materials to design medical devices and provide a greater understanding of the piezoelectric effect in the medical industry presently.
Abstract: Smart piezoelectric materials are of great interest due to their unique properties. Piezoelectric materials can transform mechanical energy into electricity and vice versa. There are mono and polycrystals (piezoceramics), polymers, and composites in the group of piezoelectric materials. Recent years show progress in the applications of piezoelectric materials in biomedical devices due to their biocompatibility and biodegradability. Medical devices such as actuators and sensors, energy harvesting devices, and active scaffolds for neural tissue engineering are continually explored. Sensors and actuators from piezoelectric materials can convert flow rate, pressure, etc., to generate energy or consume it. This paper consists of using smart materials to design medical devices and provide a greater understanding of the piezoelectric effect in the medical industry presently. A greater understanding of piezoelectricity is necessary regarding the future development and industry challenges.
TL;DR: The recent progress of biomedical applications of PDA as smart materials in biosensors, drug delivery and bioimaging, as well as tissue engineering is summarized.
Abstract: Polydiacetylene (PDA) is a kind of highly conjugated polymer with unique colorimetric and optical properties. A blue and non-fluorescent PDA can be formed upon 254 nm UV irradiation or γ-ray irradiation via 1,4-polymerization of diacetylene monomers, which will transition to red and fluorescent PDA when exposed to environment stimuli, such as pH, temperature, electric and mechanical stresses, and ligand–receptor interactions. As a result, PDA-based materials are particularly attractive for biosensing applications. In addition, the rigid conjugated backbone of PDA derived from its unique topochemical polymerization method also endows exceptional mechanical strength and stability to PDA-based biomaterials, such as liposomes, micelles, and bioscaffolds. The versatility of PDA-based smart materials enables their application in a wide range of biomedical areas. In this review, we briefly summarized the recent progress of biomedical applications of PDA as smart materials in biosensors, drug delivery and bioimaging, as well as tissue engineering. The challenges and outlooks of PDA-based smart materials were also discussed.
TL;DR: In this paper, a composite with light-induced shape memory effect, solid-state plasticity and self-healing performance was prepared by incorporating graphene oxide (GO) into a thermoset polyurethane.
TL;DR: This Review surveys the intrinsically multidisciplinary body of science targeted to realize soft, smart matter via innovations in active mechanical metamaterials and proposes ongoing research targets that may deliver the promise of autonomous, engineered matter to full fruition.
Abstract: Emerging interest to synthesize active, engineered matter suggests a future where smart material systems and structures operate autonomously around people, serving diverse roles in engineering, medical, and scientific applications Similar to biological organisms, a realization of active, engineered matter necessitates functionality culminating from a combination of sensory and control mechanisms in a versatile material frame Recently, metamaterial platforms with integrated sensing and control have been exploited, so that outstanding non-natural material behaviors are empowered by synergistic microstructures and controlled by smart materials and systems This emerging body of science around active mechanical metamaterials offers a first glimpse at future foundations for autonomous engineered systems referred to here as soft, smart matter Using natural inspirations, synergy across disciplines, and exploiting multiple length scales as well as multiple physics, researchers are devising compelling exemplars of actively controlled metamaterials, inspiring concepts for autonomous engineered matter While scientific breakthroughs multiply in these fields, future technical challenges remain to be overcome to fulfill the vision of soft, smart matter This Review surveys the intrinsically multidisciplinary body of science targeted to realize soft, smart matter via innovations in active mechanical metamaterials and proposes ongoing research targets that may deliver the promise of autonomous, engineered matter to full fruition
TL;DR: In this paper, different amounts of carbide particles were included in a shear stiffening polymer and the influences of additives were investigated through rheological measurements, and it can be stated that carbide reinforced particles result in much stiffer properties in the polymers however, the composites still keep their viscous behavior at low shear rates.