Researchers in a variety of industries — from fashion to construction and from oyster reefs to adhesives — are developing the next generation of sustainable materials to create high-tech products never before dreamed of. Some researchers are harnessing the power of living organisms, such as algal spores, fungi, and oysters, to add durability and self-healing properties to various types of construction materials, while others are innovating biofermented fabrics and adhesives derived from bacteria. The results are materials that have the potential to save money and boost performance while also being better for the planet.
Many innovations have been in construction materials, particularly concrete, driven by the fact that its production is responsible for at least 7% of greenhouse gas emissions globally each year. Concrete is made primarily of cement, water, and aggregates, with the production of cement responsible for the most environmental damage. “When we make normal cement powder in a plant, the emissions are associated with heating fossil fuels to get to a very high temperature,” explains Claire White, Ph.D., a professor of civil and environmental engineering at the Andlinger Center for Energy and the Environment at Princeton University. “When you heat the limestone, one of the main starting ingredients in [cement], past 900 degrees Celsius, it decomposes, which releases CO2.” Traditional cement is often produced at 1,450 degrees Celsius, she says.
To reduce emissions, she and collaborators at the University of São Paulo, Brazil, are tackling the problem of concrete waste, which often ends up in a landfill or gets used for lesser-value products such as the base layer of roads, she explains. The researchers’ goal is to find a way to reuse concrete to its full potential so that it is strong enough to use in new construction.
“We take the waste concrete, crush it up, and liberate what’s known as the concrete fines, the powder stuff. It’s that powder that is then heated up through the thermoactivation process,” she says. By using a composite comprising 80% recycled concrete fines and 20% virgin cement, heated to just 500 degrees Celsius, a comparable concrete is created to the traditional version, with reduced emissions. And concrete waste is kept from the landfill.
At The University of Virginia, Osman Ozbulut, Ph.D., a professor in the department of civil and environmental engineering, and Zhangfan Jiang, Ph.D., a postdoctoral research associate, are also addressing emissions from concrete production. They have found that adding graphene to concrete — whether the concrete is used in 3D printing or traditional construction methods — has the potential to reduce emissions by 30%. Graphene, made from graphite, is known for its high tensile strength.
Dr. Jiang says even adding a very small amount of graphene can greatly increase the compressive strength of concrete. Although this process may involve a little more cost upfront, she says, over time there will be savings. “When you add graphene, you improve its durability, which decreases the total life-cycle cost,” Dr. Jiang says. “The amount added is very small, 0.05% by the weight of the cement. So, you are improving its properties, and in the long-term, there is a cost advantage because you will need to use less concrete.” So far, the researchers have tested the graphene-enhanced concrete in the lab only, in concrete cubes and beams. They plan to publish a study soon that will quantify the estimated increased lifespan of the graphene-enhanced concrete.
Dr. Ozbulut and Dr. Jiang are working on another innovation in concrete production for the Virginia Department of Transportation. It involves adding 30% to 50% locally sourced calcined clay to the concrete mixture, which they have found has the potential to reduce emissions by one-third. Using calcined clay requires significantly less thermal energy than firing normal cement clinker, Dr. Ozbulut explains. “It does not involve the calcination of limestone, a process responsible for nearly 60% of cement’s carbon footprint due to the release of CO2 from calcium carbonate decomposition. Instead, calcined clay is produced by heating kaolinite-rich clays, which do not release inherent CO2 during transformation.
“We’ve done all the lab investigations, and the results are very promising,” says Dr. Ozbulut. In the second phase of their study, they plan to focus on practical implementation, including evaluating how the modified mixture performs in real-world construction settings. “When you’re building infrastructure like bridges, reliability is critical,” Dr. Ozbulut notes. “It takes time to adapt newer materials for field use, but this approach shows strong potential to support more sustainable construction.”
Wil V. Srubar, III, Ph.D., Deming Associate Dean for Innovation and Entrepreneurship in the College of Engineering and Applied Science at the University of Colorado Boulder, says he sees a strong global momentum to reduce the environmental impacts of construction materials, especially concrete. “However, these innovations must not only be technically sound, but also economically feasible and scalable to truly transform the industry,” he points out.
Help from nature
Some researchers are turning to living organisms for help in strengthening human-made structures. As head of CU Boulder’s Living Materials Lab, Dr. Srubar has created “bioblocks” made from tiny microalgae, using sunlight, seawater, and CO2 to grow carbon-negative limestone, which can be used in various building materials, including carbon-negative cement. The blocks meet and sometimes exceed specifications set forth by the global standards producer ASTM International for use as a structural and nonstructural concrete masonry unit. The lab has also designed and synthesized polymers that mimic the behavior of antifreeze proteins found in nature, making concrete less prone to freeze-thaw damage.
In some cases, structures made with the help of living organisms are protecting the environment itself in addition to facilities like buildings. Last November, researchers from Rutgers University deployed the first stretch of a self-healing oyster reef made from low-carbon concrete in the East Bay of the St. Andrew Bay Estuary, in the Florida panhandle. The project is called Reefense: A Mosaic Oyster Habitat for Coastal Defense, and its goal is to protect the shoreline and nearby Tyndall Air Force Base from tidal surges and hurricanes. Oysters naturally build reefs but have been in decline for many reasons.
Efforts like this one not only help protect the shoreline but also help rebuild valuable habitat, allowing oysters to filter the water, which in turn improves the adjacent area for seagrass beds. This creates refuges and foraging areas for many other species such as game fish, birds, and others, says David Bushek, Ph.D., a professor of marine and coastal sciences at Rutgers. It’s a win-win for the environment: more oysters, reduced storm damage.
Native oysters from the bay are beginning to colonize the 150-foot-long, 14-foot-wide reef, as hoped. The oysters will add to the resilience of the human-made reef by helping to reduce wave energy, which can erode the shoreline. “Depending on how wide the structure is, you get a 70% to 90% attenuation without the oysters. With them, that [reduction] will increase by at least another percentage,” he says. The percentage of wave attenuation will increase with oyster colonization as a result of the roughness the oysters create, Dr. Bushek explains, which increases drag or friction on the water and decreases the intensity of the wave energy.
The reef itself was made with a proprietary concrete that performs as well as traditional concrete, says Dr. Bushek. However, he is most excited about the ability of the living oysters to add to the reef’s resistive capacity over time. “If something comes in and damages the structure, it can heal itself,” he says. He expects that as sea levels rise, the oyster reef will keep pace and grow in elevation. One limitation is that oysters cannot live out of water, so the reef height is limited to mean sea level and below. But that helps dissipate the waves farther from the shore, he explains, as the reef expands three-dimensionally.
The Reefense is designed to immediately start dragging wave energy through the pores in the concrete and dampening the currents. “The shape is unique; there are ledges and things designed to improve the habitat — dark areas where oysters like to go when they are settling. There is less predation under surfaces,” he says. As more oysters colonize the reef, its strength builds.
One obstacle to wider adoption of such reefs, Dr. Bushek says, is that they must be economically competitive with traditional rock breakwater installations that offer little habitat value, or they must demonstrate that the increased cost savings from reduced storm damage over time would compensate for any increased cost in production. To that end, his team is conducting an economic assessment and identifying measures to bring down costs. The numerous environmental benefits of the reef should also be factored into any cost analysis, he says.
Plant spores and biomass
As with concrete manufacturing, the production of asphalt is another energy-intensive process that emits greenhouse gases, mostly in the ingredient-mixing phase. Jose Norambuena-Contreras, Ph.D., a senior lecturer in the department of civil engineering at Swansea University in Wales, United Kingdom, is leading efforts to make asphalt production more sustainable by testing the addition of plant spores to bitumen, the sticky, tarry substance that is a component of asphalt.
Dr. Norambuena-Contreras soaks spores of the club moss Lycopodium clavatum in recycled oils and then adds them to the bitumen. When vehicles travel across the surface of a road made this way, the spores are squeezed, releasing their oils and softening the bitumen. This allows the bitumen to flow and seep into any cracks in the roadway, sealing them.
Although the cost of the spore-infused bitumen is about 35% more than non-enhanced bitumen, according to Dr. Norambuena-Contreras, the potential benefits of the self-healing asphalt could include a longer lifespan for roads (which could result in less asphalt production, reducing emissions), reduced maintenance costs, improved safety, and better road performance.
Research into asphalt-healing capsules has been ongoing since 2020 and tested as a proof of concept in the laboratory, Dr. Norambuena-Contreras explains, but he hopes to secure funding to field test the self-healing asphalt under real road conditions. The new technology does not eliminate any jobs for road workers or require any additional training to use, Dr. Norambuena-Contreras says. “The aim is to make roads more durable over time, but human oversight will still be essential for monitoring and maintaining road conditions,” he says.
He is also testing other methods of making asphalt more sustainable, including heating and reusing waste tires in asphalt and using other types of additives, such as capsules made from brown algae spores and sunflower oil.
At King’s College London, Francisco J. Martin-Martinez, Ph.D., a senior lecturer in chemistry and natural sciences, is also experimenting with different oils to replace the traditional petroleum-based oils used in asphalt production. His lab is investigating how to obtain bio-oils using pyrolysis, or hydrothermal processes, on tree bark, agricultural waste, old tires, and other sources of carbon in waste.
He and his research team are performing computational modeling and design using the various oils. “Asphalt is a complex fluid with a countless number of molecules,” Dr. Martin-Martinez says. “It is like a puzzle. We are trying to identify similar pieces of the puzzle in waste so we can sequentially replace — piece by piece — all of the components in asphalt.”
He explains that the bio-oils improve upon traditional materials because they have antioxidant properties that help mitigate aging and eventual cracking of asphalt. His work, begun in 2020 in partnership with Dr. Norambuena-Contreras, is still occurring in the lab, but once it is scaled up to a pilot project, he will be able to better evaluate its cost compared to traditional materials.
“The oils are coming from waste [derived from biomass, agricultural waste, cooking oils, etc.] which is an advantage,” he says, “but they are competing with a very cheap material, asphalt, which comes from the leftovers of petroleum distillation.” Ultimately, because the bio-oils are sourced from biomass waste and will last longer, their carbon footprint will be lower, says Dr. Martin-Martinez.
Grass, moss, and lessons from elephant skin
Another living organism being tested for use in construction materials is fungi. Hortense Le Ferrand, Ph.D., is incorporating mycelium cultivated in the lab into construction tiles that are also made from bamboo shavings and other plant waste. She is an associate professor at the School of Mechanical and Aerospace Engineering and the School of Materials Science and Engineering at Nanyang Technological University in Singapore.
“We used bamboo because it is a local material and grows quickly, hence could add to the local circular economy,” says Dr. Le Ferrand. The idea behind the design of the tiles is to emulate the wrinkled skin of elephants, which helps the animals regulate heat. To retain heat in a building, the tiles would be placed so that the wrinkled texture is on the inside and the flat side faces out. “If we want to cool, it’s the other way around,” says Dr. Le Ferrand.
The mycelium tiles are similar in cost to more common gypsum tiles, she says, but are probably more expensive than plastic-based tiles, since the mycelium takes time to grow. Additionally, the mycelium tiles are more sustainable: They are biodegradable and resist fire, whereas plastics pollute and can release toxic fumes during a fire, she says.
Dr. Le Ferrand is now exploring the fabrication of large (25-centimeter) mycelium tiles and installing them on a wall to test their performance, in partnership with a startup in Singapore. “One barrier for [broader scale] adoption might be the need to learn the skills to grow mycelium-bound composites or simply the awareness about it,” Dr. Le Ferrand says. But she plans to explore collaboration with any interested industry and is willing to invest in refining the development of the tiles.
Many cultures have long used plant material in construction. American settlers used straw combined with plaster to build homes on the windy plains. Today, straw panels are sometimes used to build exterior walls. Now, a company called Plantd in Oxford, North Carolina, has created a plant-based alternative to oriented strand board, known as OSB, an engineered wood commonly used to construct subflooring, wall and roof sheathing, and other elements. While OSB is made by compressing layers of wood laid in specific orientations and treated with an adhesive, the Plantd boards use grasses instead, avoiding the need to harvest trees.
“Our grass-based panels outperform traditional wood-based OSB across multiple metrics,” says Nathan Silvernail, Plantd co-founder and chief executive officer. “They’re stronger, lighter, more moisture-resistant, and carbon negative — all while remaining cost-competitive,” Silvernail says. The performance advantage comes from the manufacturing process, which minimizes waste and energy compared to traditional wood processing. Other environmental benefits are substantial. “While conventional OSB requires cutting down trees that take 10 to 12 years to grow, our perennial regrows annually on the same land, which allows us to capture carbon much faster and more efficiently than forestry operations,” Silvernail explains. He adds that when the grass-based panels are installed in homes, its embodied carbon is sequestered for the lifetime of the building.
Plantd’s panels are firmly established in the market, Silvernail says, through a new partnership with D.R. Horton, one of the largest homebuilders in the United States. Plantd is ramping up production of 10 million panels over the next five-plus years. Silvernail says that partnership has helped overcome any skepticism about the product in the traditional building materials industry.
“Working with D.R. Horton has been invaluable. They’ve been a thought partner in our testing and certification process, and helped us find a third-party lab to show that the panels meet or exceed industry standards.”
Another challenge the company had to overcome was establishing a new agricultural supply chain. “This has required educating farmers about cultivation practices and demonstrating the economic benefits of growing our grass instead of traditional crops like tobacco,” says Silvernail.
Another company inspired to incorporate plant material is Respyre, based in the Netherlands, which is making a gel from moss and adding it to “bioreceptive” concrete. The concept of bioreceptive concrete emerged from interdisciplinary research at Delft University of Technology, where scientists and engineers sought to create building materials that support biological growth, says Adil Aarouss, Respyre co-founder and chief technology officer. Recognizing moss’s unique characteristics such as its ability to thrive on porous surfaces without invasive roots, the team developed a specialized concrete mix with enhanced porosity and water retention properties. The concrete is 90% to 95% recycled and the sprayed-on moss gel coating helps reduce the urban heat island effect by converting CO2 into oxygen, among other benefits. “The [moss-walls] make green in the urban environments more accessible, adding low-cost and low-maintenance options to the construction market,” says Aarouss.
Respyre products are currently only available in the Netherlands, Belgium, and Germany, so the company’s research and projects have specifically used the moss species available in those countries. “However, moss is a diverse and resilient species, capable of pioneering in a wide range of environments just as it did when it first helped create complex vegetation on our planet,” says Aarouss. He says that if moss is “growing in your city,” his company can likely grow it too. While upfront costs are modestly higher, the long-term environmental and beautification benefits will add value, says Aarouss. Respyre has now completed several successful pilots in building facades and smaller infrastructure and is collaborating with partners to integrate the moss-wall system into commercial and public projects.
“We’re seeing some exciting biological innovations find their way into buildings, and I think this is just the beginning of a biotechnology revolution in construction,” says Dr. Srubar at CU Boulder. “In a lot of ways, we are returning to our roots. We’re looking to Indigenous communities for inspiration and for examples of tried-and-true methods of building sustainable and durable infrastructure.
“Applying state-of-the-art science and engineering principles to these ancient ways of building is what is so transformative. We’re giving these ideas new life by engineering them for the 21st century.”
Spiders and microorganisms
Construction isn’t the only industry benefitting from employing biological solutions. At AMSilk in Germany, researchers have been inspired by spider silk to produce a more sustainable silk fabric that does not harm silkworms and is more environmentally sustainable, says chief scientific officer Gudrun Vogtentanz.
The challenge is to produce spider silk on a large scale, she says, but they have now scaled production quantities from kilos to tons. “We designed microorganisms to produce spider silk proteins by delivering the necessary blueprint (a modified part of the spider silk gene) directly into the organism,” explains Vogtentanz. Once coded with the genome, the microorganisms are placed in large fermenters and fed with renewable plant-based raw materials. “Proprietary host cells then start to produce our silk proteins,” she says. After the pure silk is harvested, the proteins undergo further processing and are then formulated into products such as fibers used in clothing, hydrogels for medical applications, and powders used in home care and laundry products, she says.
At AMSilk in Germany, researchers have been inspired by spider silk to produce a more sustainable silk fabric that does not harm silkworms and is more environmentally sustainable.
The new spider-silk-inspired formulations are vegan and do not contain any fossil-based raw materials. “They leave no microplastics behind and are verifiably biodegradable or recyclable,” she says.
Currently the biofabricated silk is comparable in cost to the Bombay Mori silk sold in luxury markets. “But as production scales up, prices will become more favorable, enabling us to sell our silk yarns in higher-volume premium markets — even at prices beyond traditional silk. Our highly efficient production strains and the most experienced industrial production partners will help us bring production to the necessary multiton level that is needed to be a crucial player to serve the global silk market within the next years,” Vogtentanz predicts.
Enhancing a natural polymer
As part of an experiment for the U.S. Department of Energy’s BOTTLE (or Bio-Optimized Technologies to Keep Thermoplastics Out of Landfills and the Environment) Consortium, which works to reduce single-use plastics in the environment and change the way people recycle, researchers are using bacteria to create a strong adhesive.
Led by Eugene Chen, Ph.D., in the department of chemistry at Colorado State University, the researchers have built upon a biodegradable polymer called P3HB, which is produced by bacteria, to make a more sustainable product that will help reduce petroleum-based adhesives in the environment. The polymer is not naturally adhesive, but the researchers were able to chemically reengineer its structure to create an alternative to the petroleum-derived, nonbiodegradable EVA (ethylene vinyl acetate or “hot-melt”) adhesives traditionally used in products such as shoes, electronics, vehicles, and packaging.
“Most adhesives are really hard to de-bond from the substrates they are typically used on, dooming them to the landfill or environment,” says Ethan Quinn, a researcher in Dr. Chen’s group. “One of the biggest uses is packaging, including cardboard boxes.” However, conventional adhesives can’t be recycled and take a very long time to degrade, Quinn says.
The new biodegradable, enhanced adhesives will degrade much more quickly — in one year instead of 1,000 years. Quinn adds that their research has also shown that their “super glue” is superior in strength to EVA adhesives and can be made at a similar cost. “Anything you could find made with EVA we could potentially replace with our biodegradable glue,” he adds.
One challenge ahead for putting more sustainable, innovative, bioengineered materials into large-scale use — particularly in construction — is the need for governmental and policy support.
Dr. Le Ferrand says that although there are so many feasible, sustainable, and interesting alternatives to traditional materials, plenty of barriers remain, from perceived cost to restrictive standards and various lobbies against their use. “Taxes, governmental regulations and policies, along with global awareness and a strong will to be more sustainable [would be] game changers,” she says.
