Carbon-eating bacteria could revolutionize green building

Researchers at the Swiss Federal Institute of Technology Zurich (ETH Zurich) have developed a living material that can be 3D-printed and actively absorbs carbon dioxide (CO₂) from the atmosphere. The breakthrough was announced by ETH Zurich.

The new material is a special gel that contains ancient microorganisms known as cyanobacteria. These bacteria, among the oldest life forms on Earth, are capable of photosynthesis even in low-light conditions.

The material functions through a dual carbon-binding mechanism:

• Organic bonding: The bacteria use sunlight to convert CO₂ into biomass.
• Mineral bonding: The bacteria form carbonate minerals (such as lime) during their life cycle, effectively “locking in” the carbon.

Laboratory tests showed that the material can continuously absorb CO₂ for up to 400 days, binding approximately 26 milligrams of carbon dioxide per gram. Most of the carbon is stored in stable mineral form, making the process highly efficient.

The cyanobacteria, encapsulated in a special hydrogel, remain active for over a year, ensuring long-term effectiveness.

The material is already being tested in architectural applications. For example:

• Venice Architecture Biennale: Structures called Picoplanktonics were installed in the Canadian Pavilion. Resembling tree trunks up to three meters tall, each structure can absorb up to 18 kg of CO₂ annually—the same as a 20-year-old pine tree.
• Milan Triennale: The Daphne's Skin project demonstrates how living materials can alter building appearances, forming a dark green patina of microorganisms on wood surfaces.

According to Professor Mark Tibbitt, who led the research, the material could eventually be used as a façade coating, transforming urban buildings into massive carbon sinks.

The material requires only sunlight, artificial seawater enriched with nutrients, and CO₂ from the air to grow, making the technology both environmentally friendly and energy-efficient.