Aerogel
A diverse class of ultraporous and solid materials with extremely low densities, and thermal insulating properties, employed in biomimetic and biosensor applications, construction, water distillation, and fashion.
Technology Life Cycle
R&D
Initial phase where new technologies are conceptualized and developed. During this stage, technical viability is explored and initial prototypes may be created.
Technology Readiness Level (TRL)
Prototype Demonstration
Prototype is fully demonstrated in operational environment.
Technology Diffusion
Early Adopters
Embrace new technologies soon after Innovators. They often have significant influence within their social circles and help validate the practicality of innovations.
Lightweight, solid, and translucent materials with a vast array of extreme properties, such as ultrahigh porosity, ultralow thermal conductivity, and acoustic isolation. Aerogels can help produce stable, thickened products and enable broader use of active ingredients and fragrances with greater stability and longevity, as well as improve other materials with superelastic characteristics.
Aerogels can be created by replacing liquids with gasses in silica, metal oxide, or a polymer gel. A recent, advanced version of the technology has shown strong shape memory, implying that when aerogels are deformed and cooled, they will maintain the deformed shape. At the same time, they will revert to their original form at room temperature.
One of the key benefits of aerogel is its exceptional insulating properties, which are due to its extremely low thermal conductivity. This makes it an excellent material for use in applications where heat transfer needs to be minimized, such as in building insulation, aerospace components, and cryogenic storage. In addition to its insulating properties, aerogel has a high surface area, making it useful for applications such as catalyst support, gas storage, and environmental remediation. Another advantage of aerogel is its lightweight and low density, making it ideal for use in applications where weight is a concern, such as in space exploration or high-performance clothing. However, despite its many benefits, aerogel can be brittle and fragile, which can limit its use in some applications.
They can also be applied for the design of bionic hands, capable of mimicking coordinated muscle functions when stimulated by heat. Other possible uses range from biomimetic applications to water remediation. Graphene-based aerogels, for example, can convert sunlight into water vapor at room temperature in a low-cost and efficient distiller. In fashion, aerogel is used in jackets, gloves, and hats due to aerogels' insulation properties, thus working as a flexible, hydrophobic, and durable design for winter sports clothing and outerwear.
Future Perspectives
Aerogels could be applied as a green technology on a wide scale in novel ways in diverse industries. Carbon aerogel holds excellent potential as supercapacitors and fuel cells for energy-efficient automobiles. With the advancement of complex organic aerogel compositions, aerogel can potentially serve as the base of various biosensors due to its exceptional elasticity and insulation ability, as well as become part of moisturizing skin patches due to its ability to convert sunlight into water vapor.
Image generated by Envisioning using Midjourney
Sources
Noise reduction remains an important priority in the modern society, in particular, for urban areas and highly populated cities. Insulation of buildings and transport systems such as cars, trains and airplanes has accelerated the need to develop advanced materials. Various porous materials, such as commercially available foams and granular and fibrous materials, are commonly used for sound mitigating applications. In this review we examine a special class of advanced porous materials, aerogels, and provide an overview of the current experimental and theoretical status of their acoustic properties. Aerogels can be comprised of inorganic matter, synthetic or natural polymers as well as organic/inorganic composites and hybrids. Aerogels are highly porous nanostructured materials with a large number of meso‐ and small macropores; the mechanisms of sound absorption partly differ from those of traditional porous absorbers possessing large macropores. The understanding of the acoustic properties of aerogels is far from being complete, and experimental results remain scattered. It is demonstrated that the structure of the aerogel provides a complex three‐dimensional architecture ideally suited for promising high‐performance materials for acoustic mitigation systems. This is in addition to the numerous other desirable properties which include low density, low thermal conductivity, and low refractive index. This article is protected by copyright. All rights reserved.
Aerogel fibers garner tremendous scientific interest due to their unique properties such as ultrahigh porosity, large specific surface area, and ultralow thermal conductivity, enabling diverse potential applications in textile, environment, energy conversion and storage, and high-tech areas. Here, the fabrication methodologies to construct the aerogel fibers starting from nanoscale building blocks are overviewed, and the spinning thermodynamics and spinning kinetics associated with each technology are revealed. The huge pool of material choices that can be assembled into aerogel fibers is discussed. Furthermore, the fascinating properties of aerogel fibers, including mechanical, thermal, sorptive, optical, and fire-retardant properties are elaborated on. Next, the nano-confining functionalization strategy for aerogel fibers is particularly highlighted, touching upon the driving force for liquid encapsulation, solid–liquid interface adhesion, and interfacial stability. In addition, emerging applications in thermal management, smart wearable fabrics, water harvest, shielding, heat transfer devices, artificial muscles, and information storage, are discussed. Last, the existing challenges in the development of aerogel fibers are pointed out and light is shed on the opportunities in this burgeoning field.
A biopolymer-based aerogel has been developed to become one of the most potentially utilized materials in different biomedical applications. The biopolymer-based aerogel has unique physical, chemical, and mechanical properties and these properties are used in tissue engineering, biosensing, diagnostic, medical implant and drug delivery applications. Biocompatible and non-toxic biopolymers such as chitosan, cellulose and alginates have been used to deliver antibiotics, plants extract, essential oils and metallic nanoparticles. Antibacterial aerogels have been used in superficial and chronic wound healing as dressing sheets. This review critically analyses the utilization of biopolymer-based aerogels in antibacterial delivery. The analysis shows the relationship between their properties and their applications in the wound healing process. Furthermore, highlights of the potentials, challenges and proposition of the application of biopolymer-based aerogels is explored.
A combination of laboratory experiments and numerical modelling shows that a 2–3 cm-thick layer of silica aerogel deployed over the temperate regions of Mars could maintain a surface environment conducive to liquid water all year round. Such an approach would create a hab…
John Davis, CSO of Palo Alto Networks' federal division, suggested that too many firms have given in to the hackers by resigning themselves to this reactionary approach. "Some of our industry has given up on the ability to prevent and is focused primarily on detection and response, which means, with a mindset like that, it means you're always involved in cleaning up aisle nine, as some people like to say..."
Colorful lanthanide oxide aerogels made by epoxide-assisted gelation of metal salts (image credit Lawrence Livermore National Laboratory)
A time-lapse of one of the aerogels flexing from a held-closed position back to its original straight shape. Photo by Sam O’Keefe/Missouri S&T.
Lightweight aerogels with elastic performance and tunable surface properties have made them a good alternative for smart electornic skin. However, the aerogels remain a great barrier for sensing applications because of their severe brittleness and difficult regulation of surface property. Herein, we report a superelastic aerogel originated from a rational designed waterborne poly(siloxane-benzoxazine) by using the ice template method. The three-dimensional (3D) network is constructed via the radical crosslinking and ring-opening polymerization followed by the freeze-drying process. Moreover, it also shows pronounced mechanical performance that can be compressed over 70% and recover without fracture. Beyond that, its surface property could be altered from highly hydrophilic to hydrophobic property (145° water contact angle) by adjusting the crosslinking degree of the aerogel under different curing temperatures. We further demonstrate a pressure sensor by in situ polymerization of the aniline (PANI) on the surface of the aerogel. The multifunctional properties make it an attractive material for self-cleaning electronic skin.
Cellulose nanomaterials from plant fibre provide potential applications in biomedical. The biomedical application of nanocellulose isolated from plant fibre, which is a carbohydrate-based source, is very viable in the 21st century. The essential characteristics of plant fibre-based nanocellulose, which include its molecular, tensile and mechanical properties, as well as its biodegradability potential, have been widely explored for functional materials in the preparation of aerogel. Plant cellulose nano fibre (CNF)-based aerogels are novel functional materials that have attracted remarkable interest.
Being the lightest solid materials known, and given the great variety of possible chemistries capable of yielding wet-gels, aerogels and composite aerogel materials have a tremendous potential in a wide range of applications, where high pore volume and high surface area play major roles. Today, the main commercialized application of aerogels is thermal insulation, although aerogels can be used for a huge variety of applications such as electrochemistry (super capacitors), carrier of catalysts and other active agents, filling materials, materials for tissue engineering etc. However, industrial production of aerogels is so far mostly limited to silica-based systems, limiting the possibility to prove the potential application by prototyping. In this paper first the state of the art of the aerogel manufacturing and applications are briefly discussed. Based on the current status, main knowledge gaps and challenges are identified and the future research directions from the point of view of the authors are derived. In the next future, we expect significant further development in the area of the organic and hybrid aerogel aerogels, optimization of their manufacturing processes and their transfer to the market.
Aerogel is a revolutionary material possessing unique physical properties. But despite being the lightest and highly effective against the heat, why isn’t this material being widely used?
As a chronic disease, diabetes may result in serious complications that endanger the health and life of patients. Accurate and real-time detection of blood sugar levels is of great significance for the prevention and treatment of diabetes. In this paper, an enzymatic electrochemical microfluidic biosensor for glucose detection was developed based on a three-dimensional (3D) porous graphene aerogel and glucose oxidase (GOx). A graphene aerogel was prepared by freeze-drying a graphene hydrogel and has a high electrical conductivity, the 3D porous structure provided a good near-biological condition for GOx and the increased specific surface area allowed more GOx to be immobilized on the graphene aerogel.
Wearable bioelectronic systems are one of the most important tools for human health and motion monitoring. However, there is still a great challenge to fabricate high-performance flexible devices with a conformal integration of the human body and there is no single device that can collect and correlate data simultaneously from chemical and mechanical signals of the human body. We recently developed a new method to build aerogel-based strain and sweat sensors (AB-SSS) that can effectively extract real-time information by combining involuntary human motion and chemical signals due to their gradient functionalities. These sensors provide good mechanical integrity and allow high-density power generation during subtle human motion, allowing sweat monitoring by measuring pH, ion concentration, perspiration rate, etc.
Aerogels have been steadily developed since its first invention to become one of the most promising materials for various medical and non-medical applications. It has been prepared from organic and inorganic materials, in pure forms or composites. Cellulose-based aerogels are considered one of the promising materials in biomedical applications due to their availability, degradability, biocompatibility and non-cytotoxicity compared to conventional silica or metal-based aerogels. The unique properties of such materials permit their utilization in drug delivery, biosensing, tissue engineering scaffolds, and wound dressing. This review presents a summary of aerogel development as well as the properties and applications of aerogels. Herein, we further discuss the recent works pertaining to utilization of cellulose-based aerogels for antibacterial delivery.
Creating a configurable and controllable surface for structure-integrated multifunctionality of ultralight aerogels is of significance but remains a huge challenge because of the critical limitations of mechanical vulnerability and structural processability. Herein, inspired by Salvinia minima, the facile and one-step coassembly approach is developed to allow the structured aerogels to spontaneously replicate Salvinia-like textures for function-adaptable surfaces morphologically. The in situ superimposed construction of bioinspired topography and intrinsic topology is for the first time performed for programmable binary architectures with multifunctionality without engendering structural vulnerability and functional disruption. By introducing the binding groups for hydrophobicity tailoring, functionalized nanocellulose (f-NC) is prepared via mechanochemistry as a structural, functional, and topographical modifier for a multitasking role. The self-generated bioinspired surface with f-NC greatly maintains the structural unity and mechanical robustness, which enable self-adaptability and self-supporting of surface configurations. With fine-tuning of nucleation-driving, the binary microstructures can be controllably diversified for structure-adaptable multifunctionalities. The resulting ultralight S. minima-inspired aerogels (e.g., 0.054 g cm-3) presented outstanding temperature-endured elasticity (e.g., 90.7% high-temperature compress-recovery after multiple cycles), durable superhydrophobicity, anti-icing properties, oil absorbency efficiency (e.g., 60.2 g g-1), and thermal insulating (e.g., 0.075 W mK-1), which are superior to these reported on the overall performance. This coassembly strategy offers the opportunities for the design of ultralight materials with topography- and function-tailorable features to meet the increasing demands in many fields such as smart surfaces and self-cleaning coatings.