Buildings are among the biggest climate killers in the world, with concrete in particular making a massive contribution to CO2 emissions. Together with structural steel, emissions account for 14 percent of global emissions. There is an alternative building material that is not only climate-neutral but also climate-positive: wood. You only have to let trees grow and they naturally absorb CO2 from the atmosphere and absorb it. A mature tree "eats" a ton of CO2 per year.
That alone makes wood an attractive alternative to brick and concrete, but the word "natural" doesn't have only positive connotations. The organic material can decompose again, is gnawed on by insects and does not come in any size or shape.
So scientists are working to turn the natural material into an industrial product. Scientists at Rice University in Texas have achieved the feat of making wood even more stable in this way. From natural wood, they make a sustainable wood composite that can further absorb carbon dioxide from the air, they write in their study, published in Cell Reports Physical Science.
As with all work on the subject of "super wood", a natural component is first removed. "Wood consists of three main components: cellulose, hemicellulose and lignin," said Muhammad Rahman, corresponding author of the study. "Lignin gives the wood its color, so if you remove the lignin, the wood becomes colorless."
The lignin forms the inner framework of the wood, after it is removed, highly porous metal-organic microparticles (MOFs) are introduced. "The MOF particles easily fit into and adhere to the cellulose channels," says Soumyabrata Roy, lead author of the study. The Calgary framework 20 (CALF-20) was used for the study. These microparticles are adsorption materials with very large surfaces, with which they bind carbon dioxide molecules. In this way, the wood is transformed into a turbo CO2 store. In addition to the CO2, which is already bound as the tree grows, there is now also the amount of CO2 that the MOF particles bind. The process is said to be very energy efficient. The wood material obtained in this way is stronger and harder than natural wood and is also easier to bend.
Methods are being worked on everywhere to bind CO2 artificially and thus ban it from the atmosphere. The method of trying "Super Wood" has a unique advantage. Here the CO2 is not pressed under the surface of the earth, but a useful building material is obtained, which can also replace materials that are very harmful to the climate.
Sources: Rice University, architexturez