Researchers at ETH Zurich have created a novel type of material that goes beyond mere existence. It has the capability to live, develop, and extract carbon dioxide directly from the atmosphere. This living substance was crafted through a collaboration of biology, chemistry, and engineering fields and may provide a new, energy-efficient approach to carbon capture in architectural and design applications.
Fundamentally, the material is a hydrogel rich in water and populated by cyanobacteria, some of the Earth’s ancient life forms. These tiny organisms excel at photosynthesis and can thrive even in low-light conditions. Within the hydrogel, they take in CO2, transform it into biomass, and instigate the production of solid carbonates, effectively sequestering carbon in a durable mineral form.
This offers the material an additional mechanism for CO2 capture that surpasses the longevity of biological growth alone. The hydrogel has been meticulously engineered to facilitate microbial life, allowing light transmission and the movement of water and nutrients, which keeps the bacteria active for more than 400 days during laboratory assessments. To boost efficacy, the research team employed 3D printing techniques to produce high-surface-area geometries that facilitate deeper light access and optimal nutrient distribution.
The end product is a pliable material that gradually solidifies as minerals accumulate within it, forming an actual living structure that becomes more resilient over time. Outside the laboratory, this innovative material has already made its mark in architecture. In Venice, hydrogel-printed structures were constructed into three-meter-tall columns for the Architecture Biennale. Each of these installations can capture up to 18 kilograms of CO2 annually, akin to a young pine tree.
A separate initiative in Milan is exploring the potential of the living material as a coating for wood, transforming microbial growth into a distinctive design element. This approach distinguishes itself from conventional carbon-capture methods by being passive, scalable, and visually striking. Rather than depending on extensive industrial setups or harsh chemicals, it utilizes biological processes to capture carbon in a quiet and continuous manner.
Researchers believe it could eventually be incorporated into buildings to lessen their ecological footprint over their entire life span. A study detailing the material has been published in Nature Communications.
