At ETH Zurich, researchers have created a new “living material” that passively captures CO2 from the air, much like a tree would.
The material embeds photosynthetic cyanobacteria—ancient microorganisms capable of turning sunlight, water, and CO2 into biomass—into a custom-designed hydrogel.
This structure supports long-term carbon absorption and is printable in 3D, as shown in the study, published in Nature Communications.
What sets the material apart is its ability to sequester carbon in two ways: through the bacteria’s growth (organic biomass) and by triggering mineralization, forming stable carbonates such as lime. These minerals remain locked in place and also strengthen the material structurally.
In lab tests, the material bound CO2 continuously for over 400 days, achieving sequestration rates of up to 26 mg of CO2 per gram — outperforming many existing biological and mineralisation approaches.
To keep the bacteria active, researchers optimized the material’s geometry to enhance light exposure and fluid flow using passive capillary action.
Relevant: ETH Zurich Develops New Carbon Removal Method Using Light
The research team sees applications in architecture, particularly as a CO2-binding façade coating. While still in early development, the concept has already been scaled for installations in Venice and Milan.
ETH Zurich doctoral student Andrea Shin Ling helped adapt the ‘living material’ for architectural use, printing large, tree-trunk-shaped structures capable of capturing up to 18 kg (~40 lbs) of CO2 per year — comparable to a mature pine tree.
This work represents a low-energy, biologically driven approach to carbon removal, bridging material science, architecture, and climate technology.
Read more: Tierrasphere Introduces A Pioneering Photosynthesis-Based Durable CDR Methodology
