Living ⁢Building Material Captures Carbon, Strengthens Itself

A groundbreaking new material developed by researchers at ETH Zurich harnesses⁤ the power of ‍cyanobacteria to absorb carbon dioxide​ adn self-reinforce, offering a sustainable solution for future construction.

Cyanobacteria, among the ‌planet’s oldest life forms,⁢ possess a⁣ remarkable‍ ability to photosynthesize, converting ⁢carbon dioxide and ⁢water‌ into biomass even in low light conditions. Now, scientists are leveraging this ancient biological process to create a novel ​building material that not only ⁤sequesters carbon but also enhances its ‌own structural integrity.

Cyanobacteria: Nature’s Carbon Capture ⁤Specialists

“We’ve developed a living material that can grow and change⁤ over time,” explains Professor Robert Tibbitt, head of the research group. “But also in‌ the form of minerals-a special property of these cyanobacteria.”

Yifan Cui, a doctoral student and lead author of ‌the study, elaborates on the cyanobacteria’s unique capabilities. “Cyanobacteria are among the oldest life‌ forms in the world. They are highly efficient at photosynthesis and can utilize even the weakest light to produce biomass from⁤ CO₂ and water.”

Crucially, as a byproduct of photosynthesis, these microorganisms alter their external chemical environment, causing solid carbonates, such as lime, to precipitate. These minerals act as an additional carbon sink, storing CO₂ in a more stable form than biomass alone.

Self-reinforcing and Carbon-storing Properties

“We utilize this ability specifically in our material,” says Cui. ⁣A‌ notable practical advantage of this process is that the minerals are deposited within the material itself, mechanically⁤ reinforcing it.This means the cyanobacteria actively harden the initially soft hydrogel​ structures​ over time.

Laboratory tests have demonstrated ‍the material’s sustained⁤ carbon-binding capacity. Over a period⁤ of​ 400 days, it​ continuously ​absorbed CO₂,‌ with the majority of ⁤this sequestration occurring in mineral form.The material captured approximately 26 milligrams of CO₂ per gram, a figure that considerably surpasses many ‍other biological ⁢carbon capture methods and is comparable to the chemical mineralization of recycled concrete (around 7 mg CO₂ per gram).

The foundation of this innovative material is a hydrogel-a gel composed of cross-linked polymers with a ‌high water content. Tibbitt’s team carefully selected the polymer network to facilitate the transport of essential ‌elements: light, CO₂, water, and nutrients. This design ensures the cyanobacteria remain evenly distributed within the material without escaping.

Optimizing for Longevity and Efficiency

To maximize the ‌lifespan and photosynthetic efficiency of the encapsulated ‌cyanobacteria, the researchers employed advanced 3D printing techniques. They optimized the geometry of the structures to increase surface area, ​improve light penetration, and enhance nutrient flow.

“In this way,we created structures that enable light penetration and passively distribute nutrient fluid throughout the body by capillary forces,” explains⁤ co-first author Dalia dranseike.This thoughtful design‌ has resulted in encapsulated cyanobacteria ​that remain productively alive for over a year,a testament⁢ to the material’s‌ biocompatibility and the researchers’ ‍meticulous engineering.

Infrastructure as a Carbon Sink

The researchers envision their living material as a low-energy, environmentally amiable solution‍ capable of capturing atmospheric CO₂ and complementing existing chemical carbon ‍sequestration processes.

“In the future, we want to investigate how the material can be used as a coating for building façades to bind CO₂ throughout the entire life ‌cycle of a building,” Tibbitt states.

While widespread application is still some way off, the concept has‍ already captured the imagination of architects, who have begun‌ exploring initial interpretations of this living building ‍material in experimental projects. ⁢This fusion of‍ biology and ‌construction holds immense promise for creating more sustainable ‌and carbon-negative urban environments.