Official video (in German) of STO In Aevero aerogel insulation boards. Credit: STO.

One of the promises of your basic silica-based aerogel is that it would make a fantastic component in insulation systems—but there have always been a lot of manufacturing and processing “ifs” involved. Nevertheless, several companies are starting to make headway with emerging commercial products.

Before I get into the details, I always try to point out that in the big picture the importance—in terms of energy consumption—of improved building insulation varies among regions of the globe. While it is a second-tier concern in North America, the energy-consumption pattern in many European nations is dominated by heating. Germany is one of the best examples, where well over 25 percent of the nation’s energy consumption goes into residential and commercial space heating. Much of the problem is related to the age of the building stock. Besides the heat leakage problems that come from very old buildings, remediation is also a challenge because of sheer space limitations.

Thus, while the availability of aerogel-containing insulation panels and systems may not be front-page news in the United States, it is a fairly big deal in Europe (where the EU is already funding a major research and commercialization initiative). It’s worth keeping this in mind as you read about the developments below, and illustrated in the video above.

The first is that an internal insulation and finishing system developed by STO AG—”STO in Aevero”—recently received the “Award for Product Innovation” at the BAU 2013 trade fair. At least in terms of product recognition, this is a nice accomplishment because BAU, as far as I know, is the world’s largest expo for architecture, materials, and systems. STO’s system uses aerogel develop by Cabot.

Sixty companies were part of the competition, vying for three prizes and six awards. The STO/Cabot system won the events “Investing in the Future” award, which apt. A Cabot news release describes the product as a “super slim system is comprised of a composite board that combines Cabot’s aerogel particles for superior energy-savings performance with STO’s binder and composite technology. This results in an insulation board that offers greater energy efficiency than traditional materials. Cabot’s aerogel enables an ultra-low thermal conductivity of 0.016 W/mK applied in very thin insulation thicknesses from 10 to 40 millimeters (R3.5 - R14).”

Here is a summary of STO In Aevero’s properties:

• Thermal conductivity: 0.016 W / (mK)
• Compressive strength: ≥ 100 kPa
• Water vapor diffusion resistance factor μ: 10
• Tensile strength perpendicular to faces: ≥ 20 kPa
• Density: ≥ 150 kg / m³
• Panel thicknesses: 10, 15, 20, 30, 40 mm
• Sheet size: 580 x 390 mm
• Material class B2 according to DIN 4102 (B1 in the system)

STO’s contribution is significant in that it had to design and manufacture a composite board that, besides incorporating the aerogel, also addresses permeability and vapor control and delivers a product in a thin form factor. STO also has developed some important installation methodologies, and leveraged its experience with installing high-quality facade, plasters, paints and rain screen-cladding systems.

In the Cabot release, Raj Chary, vice president and general manager for Cabot Aerogel says, ”[STO's] modern, intelligent solutions in reconstruction, renovation and renewal work are helping architects and builders meet the highest regional and industry standards for energy conservation, [and to] help deliver energy efficient renovation solutions for historical buildings as well as new construction.”

One frustrating thing that unfortunately is lacking in these announcements is pricing/installation cost information relative to traditional insulation.

While STO and Cabot seem to be staking out the building sector, Aspen Aerogels continues to refine its products for industrial application. Aspen was one of the first companies that demonstrated a flexible insulation system that could, for example, be used as a wrapable barrier around pipes. Aspen and others saw a business opportunity with insulating pipes that pass through cold regions, such as the petroleum pipelines that cross Alaska.

Apparently the company was also keeping an eye on high-temperature applications, too. Recently Aspen, announced a new high-temperature insulation, Pyrogel XT-E. A news release from the company indicates that the new product is a variation of if the existing XT product, and that it is being aimed at uses refining, petrochemical, power and other facilities. Given the recent boom in the drilling and refining industries, a product aimed at this sector makes a lot of sense.

In the Aspen release, Don Young, president and CEO, says Pyrogel XT-E is “the most effective high-temperature insulation material in the industrial market and improves our customers’ ability to use our product in the most demanding environments.”

A document (pdf) on the Aspen websites says that it is available in rolls of sizes of 850 and 1,500 square feet, is available in 5 and 10-millimeter thicknesses, and has a density of about 12.5 pounds per cubic foot.

Like Aspen’s other products, the Pyrogel XT-E comes in rolls that makes it a “labor saver.” Aspen also says it has been able to significantly reduce the dust that comes from installation. It says its flexible blanket form is up to five-times thinner than competing insulation products and can serve in applications that range from -270 °C to 650°C.

No pricing was mentioned for the Aspen product, either.

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Strategic Materials Advisory Council cautions DOD against stockpiling Chinese rare earths

The Strategic Materials Advisory Council has cautioned the Department of Defense to avoid the risky mitigation strategy of stockpiling strategic and critical materials from China. The DOD recently completed its biannual “Strategic and Critical Materials 2013 Report on Stockpile Requirements,” which recommended stockpiling $120.43 million of heavy rare earth elements—materials produced only in China. ”The root cause of these material shortages is our ongoing dependence on Chinese suppliers,” says Council Executive Director Jeff Green. “While it is encouraging that DoD acknowledges these risks, we urge DOD to move from theoretical studies to the only appropriate and permanent solution: the creation and nurturing of a US-based rare earth supply chain.” The rare earth stockpile recommendation represents over one-third of a $319.74 million stockpiling plan to mitigate a $1.2 billion shortfall of 23 strategic and critical materials. This encouraging recommendation contrasts dramatically with previous DOD assessments that asserted domestic sources could meet all military requirements by 2013, except for yttrium, and that substitution would be a viable approach to risk mitigation for heavy rare earths.

‘Smart’ chemo drug goes easy on fertility

A new chemotherapy drug in the form of nanoparticles is less toxic to young women’s fertility but extra tough on cancer, say researchers. “Our overall goal is to create smart drugs that kill the cancer but don’t cause sterility in young women,” says Teresa Woodruff, a co-principal investigator of the study and chief of fertility preservation at Northwestern University. The chemotherapy drug, arsenic trioxide, is packed into a very tiny Trojan horse called a nanobin. The nanobin consists of nano-size crystalline arsenic particles densely packed and encapsulated in a fat bubble. The fat bubble, a liposome, disguises the deadly cargo-half a million drug molecules. The fat bubble is the perfect size to stealthily slip through holes in the leaky blood vessels that rapidly grow to feed tumors. The local environment of the tumor is often slightly acid and it’s this acid that causes the nanobin to release its drug cargo and deliver a highly effective dose of arsenic where it is needed. The scientists show this approach to packaging and delivering the active drug has the desired effect on the tumor cells but prevents damage to ovarian tissue, follicles, or eggs. Arsenic trioxide was approved a few years ago for treating some types of blood cancers such as leukemia in humans, but the researchers think the arsenic trioxide nanobins can be used against breast cancer and other solid tumors.

Harvesting unused energy with flat, printed thermoelectrics

At the Hannover trade fair, Fraunhofer researchers are now presenting a new manufacturing process with which these thermoelectric generators can be cost-effectively produced in the form of large-area flexible components from non-toxic synthetic materials. The scientists‘ vision is described by Aljoscha Roch of the Fraunhofer Institute for Material and Beam Technology IWS in Dresden: “Thermoelectric generators (TEG) currently have an efficiency of around eight percent. That sounds very small. But if we succeed in producing TEG cost-effectively, on a large scale and from flexible materials we can install them extensively on the insides of the concave cooling tower wall. In this way, through the enormous amount of energy produced in the huge plants—around 1500 liters of water evaporate per minute—we could generate large quantities of electricity.” The scientists have succeeded in producing TEGs by means of a printing process. The miniaturized generators can not only be produced cost-effectively, on large surfaces and in a flexibly manageable manner, but an additional major advantage is that the materials used are environmentally-friendly. “TEG are today largely produced by hand from toxic components which contain lead for example. We are now using modern 3D printing technology and harmless polymers (plastics) that are electrically conductive,” explains Roch. The IWS researchers are demonstrating the printed TEG for the first time in a cooling tower model at the Hannover trade fair.

To trap a rainbow, slow down light

Researchers have developed a “hyperbolic metamaterial waveguide” that halts and ultimately absorbs each frequency of light, at slightly different places in a vertical direction, to catch a “rainbow” of wavelengths. The technology is essentially an advanced microchip made of ultrathin films of metal and semiconductors and/or insulators. ”Right now, researchers are developing compact light absorbers based on optically thick semiconductors or carbon nanotubes. However, it is still challenging to realize the perfect absorber in ultrathin films with tunable absorption band,” says Qiaoqiang Gan, an assistant professor of electrical engineering at University at Buffalo. Gan previously helped pioneer a way to slow light without cryogenic gases. He and other researchers at Lehigh University made nanoscale-sized grooves in metallic surfaces at different depths, a process that altered the optical properties of the metal. While the grooves worked, they had limitations. For example, the energy of the incident light cannot be transferred onto the metal surface efficiently, which hampered its use for practical applications. As reported in the journal Scientific Reports, the waveguide solves that problem because it is a large area of patterned film that can collect the incident light efficiently. Researchers say the technology could lead to advancements in an array of fields, such as preventing crosstalk in electronics or energy-harvesting devices.

Carnegie Institution releases ‘Advances in Matter Under Extreme Conditions’ report on 2012 HPCAT Workshop

The High-Pressure Collaborative Access Team (HPCAT), a group linked to the Advanced Photon Source (APS) facility at the Argonne National Lab, held a workshop Oct. 10-12, 2012, to review the successes of HPCAT over the past 10 years, as well as opportunities for addressing key grand challenges in future of extreme conditions science. During the past decade, HPCAT has taken advantage of the nation’s most brilliant high-energy synchrotron source and developed a multitude of integrated synchrotron radiation techniques optimized for high-pressure research. These X-ray probes, integrated with hydrostatic or uniaxial compression, static or dynamic loading, resistive or laser heating, and cryogenic cooling, have enabled users’ investigations of structural, vibrational, electronic, and magnetic properties at high pressure and high/low temperature that were not possible a decade ago. The workshop consisted of over 120 people from the US and abroad. Emerging from the workshop and its discussions is a clear signal of the outstanding opportunities for the future of extreme conditions science at the APS in the years to come. The report is approximately 120 pages (pdf)

Superconductivity: denser, better

New experiments set the record of the superconducting transition temperatures for a new family of iron-based selenide superconductors. These materials were recently found to superconduct below 30 K, but their transition temperatures decline until approaching absolute zero temperature with the application of pressure. Now Carnegie scientists Xiao-Jia Chen, Lin Wang, and Ho-Kwang Mao, in collaboration with scientists from from the National Institute of Standards and Technology, the Chinese Academy of Science, and Zhejiang University, have uncovered reemerging superconductivity above 48 K in iron selenides upon further compression. The disappearance of superconductivity in the low-pressure cycle and the re-emergence of superconductivity with higher transition temperatures in the high-pressure cycle reflect detailed structural variances within the basic unit cell itself. The two superconducting domes were likely the result of different charge carriers. Finding the reentrance of superconductivity at 48 K in the new iron family of superconductors points to the possibility of achieving similar higher transition temperatures at ambient pressure through some structural modifications

Researchers find that tiny nanowires can lift liquids as effectively as tubes

New research carried out at MIT and elsewhere has demonstrated for the first time that when inserted into a pool of liquid, nanowires - wires that are only hundreds of nanometers across - naturally draw the liquid upward in a thin film that coats the surface of the wire. The finding could have applications in microfluidic devices, biomedical research and inkjet printers. Although this upward pull is always present with wires at this tiny scale, the effect can be further enhanced in various ways: Adding an electric voltage on the wire increases the force, as does a slight change in the profile of the wire so that it tapers toward one end. The researchers used nanowires made of different materials—silicon, zinc oxide and tin oxide, as well as two-dimensional graphene—to demonstrate that this process applies to many different materials. The results are published in the journal Nature Nanotechnology by a team of researchers led by Ju Li, an MIT professor of nuclear science and engineering and materials science and engineering, along with researchers at Sandia National Laboratories in New Mexico, the University of Pennsylvania, the University of Pittsburgh, and Zhejiang University in China. Several brief videos of the nanowires in action have been posted on YouTube by Li’s research group.

Even graphene has weak spots

Even graphene, the Superman of materials, has its kryptonite: Defects in polycrystalline graphene will sap its strength. The unexpected weakness is in the form of a seven-atom ring that inevitably occurs at the junctions of grain boundaries in graphene, where the regular array of hexagonal units is interrupted, report researchers. At these points, under tension, polycrystalline graphene has about half the strength of pristine samples of the material. New research shows defects in polycrystalline forms of graphene will sap its strength. The new calculations could be important to materials scientists using graphene in applications where its intrinsic strength is a key feature, like composite materials and stretchable or flexible electronics. The team calculated that the particular seven-atom rings found at junctions of three islands are the weakest points, where cracks are most likely to form. These are the end points of grain boundaries between the islands and are ongoing trouble spots.

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We always like to keep an eye out for interesting advanced in metal oxides, and a paper just posted on the online Science Express reports that strides have been made in developing a process to use thin amorphous mixed-metal oxide films to deliver an improved catalyst for hydrogen generation via electrolysis (oxygen evolution reaction).

The benefits of using crystalline metal oxides, such as IrO₂ and RuO₂, and mixed-metal oxides as catalysts for large-scale electrolysis are already known. Similar benefits have also been demonstrated with amorphous phases. But, the catch with using the latter has been coming up with a method to produce homogeneous amorphous mixed-metal compositions.

Now, a group of researchers from the Department of Chemistry and Centre for Advanced Solar Materials at University of Calgary say they have a low-temperature process, based on photochemical metal-organic deposition (PMOD), that can produce films containing a homogeneous distribution of metal oxides with compositions that can be accurately controlled. The group is led by Curtis P. Berlinguette, director of the Centre, the goal of which is to conduct inorganic chemistry research aimed at increasing the contribution of solar energy to the global energy mix.

Which is not to say that there haven’t been other methods to produce amorphous metal oxide catalysts. Electrodeposition techniques exist for this, but their applicability varies widely from metal to metal. Control problems with mixed metals also make it difficult to use electrodeposition to tailor the voltage protocols for catalysts. These are significant problems because experience has shown that a mixed-metal catalyst is preferable over single-composition catalysts.

PMOD is a fairly well known method that uses an amorphous metal organic precursor thin film. The film is irradiated under ambient conditions. The resulting photoreaction leads to the formation of metal oxide thin films in the presence of oxygen. In this research, the group used spin coating and PMOD to make homogeneous thin films of amorphous mixed-metal oxides of iron, nickel, and cobalt in various combinations (e.g., a-FeO_x, a-NiO_x, a-CoO_x, a-FeCoO_x, a-FeNiO_x and a-FeCoNiO_x).

The results? In brief, they authors report that the catalytic properties of a-Fe₂O₃ prepared with their PMOD technique “are superior to hematite, while those of a-Fe_100-y-zCo_yNi_zO_x are comparable to noble metal oxide catalysts currently used in commercial electrolyzers.”

Understandably, they are happy with the first generation of these thin films. “[W]e contend that the PMOD technique opens an entirely new parameter space for discovery and optimization of new heterogeneous electrocatalysts,” they write.

According to a university press release, the professors have patented the technology and set up a spin-off company, FireWater Fuel Corp. Firewater Fuel hopes to have a large scale electrolyzer ready for the commercial market by 2014 and a smaller scale prototype ready to test for home markets by 2015.

The paper is “Photochemical Route for Accessing Amorphous Metal Oxide Materials for Water Oxidation Catalysis” (doi:10.1126/science.1233638).

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Thermo-Calc Software releases new version of its computational thermodynamics software

Thermo-Calc Software AB announced the release of Thermo-Calc 3.0, which constitutes the third generation of its popular computational thermodynamics software. Thermo-Calc is a powerful software package used to perform thermodynamic and phase diagram calculations for multi-component systems of practical importance. Calculations are based on thermodynamic databases produced using the CALPHAD method. Databases are available for Steels, Ti-, Al-, Mg-, Ni-alloys, multi-component oxides and many other materials. ”Our main ambitions for this new version of Thermo-Calc have been to unify the two earlier versions of Thermo-Calc (i.e. Thermo-Calc Classic and Thermo-Calc Windows) into one application, and to create a framework that is suitable for future extension with additional modules and functionality that will integrate more closely with our other software tools such as DICTRA and TC-PRISMA,” says Anders Engström, CEO of Thermo-Calc Software AB.

Wind in the sails: Turbine maker Ghrepower makes the difference by creating jobs amid tough economic climate

When Ghrepower, a Shanghai-based manufacturer of small and medium-size wind turbines, decided to set up a subsidiary in Swansea, Wales, in 2011 to tap into the British wind turbine market, it did not realize how much of an impact it would make on the local community. One thing of great help to Ghrepower was the GO Wales Work Placements scheme, created to help Welsh graduates find work. Graduates participating in the scheme work at companies located in Wales for between six to 10 weeks, during which time the Welsh government contributes up to 100 pounds. When the placement period ends, the employers can offer the workers long-term jobs if they wish to. “We expanded overseas because the wind turbine market in China is restricted by China’s immature smart grid system, which is the infrastructure essential for delivering energy generated from wind farms to people’s homes,” Deng says. “As our products are manufactured in China, we have certain cost advantages. For example, a crucial material for the wind turbines battery is a magnet, which in turn relies on rare earth materials. As China produces rare earths, we have a cost advantage,” he says. At the same time, Deng points out that some of its extra functions single it out from its competitors. For example, the wind turbines’ propeller blades can change shape in response to the amount of wind available. “This technology is common for large scale wind turbines, but quite rare for small and medium-scale turbines, and makes us unique.

Cabot Extends Dow Corning relationship with capacity expansion in Europe

Cabot Corp. completed an expansion project at its fumed silica facility in Barry, Wales. Production capacity at the site has been increased by 25 percent. The expansion is part of a three-year plan started in 2011 to increase Cabot’s global fumed metal oxide capacity by 35-40 percent. This expansion project is an extension of Cabot’s long-term relationship with Dow Corning. Furthermore, the increased production capacity supports Cabot’s growth in the rising global silicones market. This market is poised to grow at 6-9 percent per year over the coming decade. Through the expansion project, Cabot can now use a wider range of silane raw materials to make a broader portfolio of products to meet silicones and other market needs. Cabot and Dow Corning have worked closely together in Barry since 1991, when Cabot built its fumed silica facility adjacent to Dow Corning’s silicone monomer plant. As part of a highly interdependent and collaborative “fence-line” relationship, Dow Corning provides Cabot with silanes that are converted to fumed silica for Dow Corning’s compounded silicones applications, as well as for other customers and applications including electronics, adhesives, and composites.

Orbite Aluminae Inc. and Veolia Environmental Services create partnership to recycle and remediate red mud from alumina production

Orbite Aluminae Inc. and Veolia Environmental Services signed an exclusive worldwide collaborative agreement for the treatment and recycling of red mud generated by industrial alumina production using the Bayer process. The terms of the partnership include the construction of the first plant to treat red mud using Orbite’s patented process. Red mud often remains stored in situ, which increases the risk of accidental spills. To meet this environmental and complex challenge facing the aluminum industry, Orbite and Veolia Environmental Services endeavour to bring the solution to treat the red mud stockpiled around the world in an economically and socially sustainable manner. These technologies allow for the extraction of smelter-grade alumina and high-purity alumina, as well as other products such as rare earths and rare metals, from various feedstocks including aluminous clay and bauxite, all without producing red mud. Veolia Environmental Services is the only worldwide integrated operator covering the entire value chain of waste management (collection, sanitation, treatment and recovery).

Reco2, a new answer to the energy saving from Sacmi

Sacmi has recently added to its long list of innovations for the sanitaryware sector with the introduction of a new brand, Reco2. The machine technical specifications allow for very considerable savings, minimization of energy consumption and reduction of polluting emissions. Sacmi’s system solutions which provide pre-drying stations enabling the energy consumption of the production line to be further reduced while, at the same time, improving health and safety in the workplace. With Sacmi’s plants customers can count on a reduction in production cycle times of 40%, in storage space requirements of 30% and in total energy costs of the complete pre-drying and drying process of up to 50%. Furthermore, the presence in glazing booths of innovative dry filters provides for the elimination of waste water and, therefore, treatment costs.

PPG launches online glass education center

PPG Industries has launched the PPG Glass Education Center, a comprehensive website to help architects, specifiers, students, and construction industry professionals learn more about designing, specifying and building with glass. Divided into three sections—glass topics, glass FAQs and glossary—the PPG Glass Education Center features a compelling mix of videos, colorful illustrations and educational features that address issues such as preventing thermal glass breakage, specifying IGUs, how low-e glass works, and how heat-treated glass differs from heat-strengthened glass. The Glass Education Center is not designed as a promotional or marketing tool. The site’s existing content is based on the most frequently asked questions PPG fields on its website, during sales calls and through its call center, and new educational material will be added continually. In addition to hosting five short videos (3 to 6 minutes each), the Glass Education Center contains an extensive glossary of industry terms and nearly two dozen frequently asked questions covering low-e glass, glass safety issues and more. Six more videos will be added to the site before July, along with content driven by architects’ questions and input.

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(a) Photograph of new UFAs with diverse shapes; (b) a 100 cm³ cylinder standing on a flower like “dog’s tail”; (c) a ~1000 cm³ pie pan-shaped cylinder (21 cm in diameter and 3 cm in thickness). Credit: Gao et al.; Advanced Materials.

I suspect this story may seem a little like old news to some readers, but a lot of the pop-sci reporting in the last few days about a new ultralight aerogel (actually, a UFA or ultra-flyweight aerogel, i.e., less than 1 mg cm⁻³) has missed the point by a wide margin. The big takeaway from this story, as documented in a new Advanced Materials paper, is that the graphene–carbon nanotube (CNT) aerogel is relatively easy to make, appears to be easily scalable, and is moldable into any shape. Moreover, the new UFA, besides having ultralow density, also is extremely flexible and elastic—with the elasticity independent of temperature—and is thermally stable, a good electrical conductor, hydrophobic, and capable of absorbing extremely high capacities for organic liquids and phase change materials.

Now, certainly, there is a significant gee-whiz factor for gaining the “world’s lightest material” title, an achievement based on a density of 0.16 mg cm⁻³, accomplished by the research team at Zhejiang University headed by Gao Chao.

The group’s material is not the first UFA. Within the past 18 months, other researchers have constructed nickel foams with density of 0.9 mg cm⁻³ (via electroless plating and subsequently etching away a polymer template), and another group constructed an aerographite with a density of 0.18 mg cm⁻³ (via a ZnO template-based chemical vapor deposition approach). But, both groups’ dependency on a template also creates enormous limitations to scalability. Sol-gel-derived, low-density aerogels can be made on fairly large scales, but with sol-gel processes it is difficult to control the dimensions of the structures.

Gao’s group, instead, uses a process that involves freeze-drying aqueous solutions of CNTs and giant graphene oxide (GGO) sheets, followed by chemical reduction of graphene oxide into graphene using hydrazine vapor. The researchers named their method a “sol-cryo” approach and note in their paper that it is easy to make large samples:

Because of the simplicity of assembly process in our template-free “sol-cryo” methodology and the large-scale availability of GGO and CNTs, the integrated all-carbon aerogels with desired densities and shapes such as rods, cylinders, papers and cubes were readily accessible. More significantly, UFAs can be easily manufactured in a large-scale. For example, a UFA cylinder up to 1000 cm³ was made with a mold of 1-liter plate.

A story on the university’s website reports quotes Gao saying, ”With no need for templates, its size only depends on that of the container. [A] bigger container can help produce the aerogel in bigger size, even to thousands of cubic centimeters or larger.” The story also reports that Gao believes ”the value of this achievement lies not in the record but in its simple way in developing the material and the superior performance exhibited.”

Briefly speaking, the microstructure of the material is a 3D porous framework constructed with cell walls of randomly oriented, crinkly graphene sheets and CNT “ribs.” The macropores ranged from hundreds of nanometers to tens of micrometers. The authors of the paper say the properties of the UFA derive from the graphene-CNT synergy: “Giant graphene flakes build a framework with macro-pores, making the aerogel ultralight; the coating of CNTs reinforces the relatively flexible graphene substrate and endows their intrinsic elasticity to the coorganized aerogel.”

One of the UFA’s interesting properties is its elasticity that allows it to be repeatedly compressed and returned to its nearly original size. This sponginess comes in handy in combination with another property: It can rapidly absorb up to 900 times its own weight in oil or other organic liquids. For example, one gram can absorb 68.8 grams of organics per second. The elasticity remained the same in tests that ranged from −190 to 300°C. The elasticity also remained after researchers annealed the UFA at 900°C for five hours.

There are probably many ways the elasticity and absorbability can be useful, not the least of which is that, because of its hydrophobicity, it could be a reusable medium to soak up oil spills on lakes and oceans. Gao says in the university story, “Maybe one day when oil spill occurs, we can scatter them on the sea and absorb the oil quickly. Due to its elasticity, both the oil absorbed and the aerogel can be recycled.” (Another Chinese research group working at Tsinghua and Peking Universities published a paper in 2010 about the use of CNTs for oil spills, and I suspect that there is some overlap between the work of the two groups.)

Another property of the UFA is that it has elasticity-dependent electrical conductivity. For example, they report connecting an LED lamp top the UFA bulk, and “its brightness fluctuates upon compressing and releasing the aerogel. This phenomenon promises the application of UFAs as pressure-responsive sensors.”

They also say that by loading the UFA with tiny amounts of certain liquids (say, CCl₄ or 1-hexadecanol), they can make conductive composites with very high electrical conductivity compared to just CNT- or graphene-based composites.

Video of variable conductivity of UFA demonstrating current change to LED when aerogel is compressed and released. Credit: Gao et al.; Advanced Materials.

Gao and the other authors also suggest the UFA could find use as supercapacitors and catalyst beds, but another intriguing application they only hint at is its use as a medium that enhances phase-change energy storage materials. For example, unlike other composites, a UFA-paraffin combination delivers higher phase-change enthalpy (ΔH) than ordinary paraffin.

These applications may only be the beginning. When it comes to learning how to leverage the properties of their fluffy stuff, the researchers say their new UFA is “just like a new-born baby.” A baby that was, perhaps, born with a silver spoon in its mouth.

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