When Timothée Boitouzet studied architecture in Japan, where buildings must survive earthquakes, understood that the next intelligent material could be what humans have used for thousands of years: wood.
"In France, we build more with concrete and stone than with wood"he said. “When I got in touch with Japanese building culture I understood how to build fantastic structures with wood. This material that we consider anything but innovative is actually super smart. The true material of the future. This is what tied me to the transparent and augmented wood project. "
In 2016, Boitouzet founded in France woodoo, a materials science company based in Paris. Woodoo modifies the wood to give it new properties. His goal is to transform the construction industry by replacing, for example, steel with wood.
Unlike other building materials, such as stone or cement that contains sand, wood is a renewable resource, making it a sustainable building material, he said. Boitouzet.
We manage trees intelligently
Building more with trees offers both an opportunity and a responsibility. The opportunity is to help curb the large carbon footprint of the construction sector, which is accelerating climate change. A recent report from the World Green Building Council estimates that 11% of global carbon emissions come from construction materials and processes over the entire life cycle of the building. Since trees contain carbon, using wood in buildings is a way to store carbon. If you want to make augmented wood a material of the future, the responsibility is to manage the use of trees wisely, taking care to plant (and plant many) more specimens than are needed for construction.
Transparent wood, a turning point in materials
By extracting the lignin from wood, a substance that makes up its cell walls, and replacing it with a specific type of polymer, wood becomes a new transparent material. “It's weatherproof, more fire resistant, three to five times stronger. And then it's transparent, ”says Boitouzet.
Don't underestimate this property: Thanks to the characteristics of the polymer added to replace lignin, light passes through the wood and opens up to a world of possible applications.
Augmented reality, "augmented" wood
So far, car manufacturers have shown the greatest interest in its transparent wood.
Currently, through a project called Woodoo Augmented Wood, the company is working on the integration of electronics in its “touch” wood, through collaboration with industry partners. The material of the future, which transmits light, will become an integral part of special “tactile dashboards” in cars, panels that will incorporate controls and displays.
Woodoo sees the automotive industry as a gateway to bringing its products to market, while introducing lighter wood products that produce less emissions than traditional panels.
Boitouzet isn't the only one excited about the possibilities offered by wood. Lars Berglund, professor of wood and composite materials at the KTH Royal Institute of Technology in Sweden, has discovered that there are many uses for transparent and resistant woods.
"It's an area that needs a lot of creativity to innovate, because people have been working on wood technology for hundreds of years", said Berglund.
While other research has mainly sought to remedy its shortcomings, such as its sensitivity to water, he and his team have focused on other characteristics. Their focus is on the use of clear wood for engineering applications.
The professor. Berglund uses wood as a model for nanotechnology: how Boitouzet eliminates lignin, introduces a polymer and adds other technologies to increase its functionality and make the material transparent.
The bright ceiling
The application currently being studied by Berglund's team is to embed quantum dots in wood to create light-emitting diodes (LEDs). "The idea is to have, for example, a wooden ceiling that lights up completely"he said.
Unlike a point light, the light of the transparent wood is diffused, more natural and comfortable to observe, says prof. Berglund. Quantum dots are a collection of semiconductor atoms, a few nanometers wide, which illuminate when exposed to UV light.
These panels are just one of many possible applications for transparent wood as a material of the future.
Wood can also form the basis for electrochromic windows. “Smart windows” that can block light when electricity passes through.
Berglund believes that this new generation wood can also be used in the energy sector. "We can improve the efficiency (of solar cells) because the dispersion of light (inside the wood) makes them travel a longer path: in other words you can absorb more energy"he said.
Using a phase change material instead of a polymer to replace the lignin turns wood into an energy storage device. During the day, this "wooden battery" can absorb heat, but at night, as temperatures cool, the phase change material crystallizes, releasing heat.
The challenge: scalability and environment
"How do you go from processing in the laboratory, where you have tight control over your nanostructure, to something that can be done on an industrial scale?" asks prof. Berglund. Scalability and the search for business partners are generally a problem with any new development, and transparent wood is no exception.
Another crucial mission is to make augmented wood even more ecological. One way to do this would be to keep as much lignin as possible, instead of discarding it. "If you remove it, you are adding a chemical step that costs energy and requires solvents", says Berglund.
That's why his team is focusing on using a greener polymer in the materials. "So far the ones used have been petroleum based to better bind the wood, but now we are working with a bio-based polymer."