Dual carbon sequestration with photosynthetic living materials

ETH Zurich researchers have developed a groundbreaking "living material" that actively captures carbon dioxide from the atmosphere through two mechanisms: biomass production and mineral formation[^1][2].

The material combines cyanobacteria (photosynthetic bacteria) embedded within a printable hydrogel matrix. The cyanobacteria convert CO2 into biomass through photosynthesis while simultaneously triggering the formation of solid carbonate minerals - a process called microbially induced carbonate precipitation (MICP)[^1].

Key achievements of the material include:

• Sequestered 2.2 mg of CO2 per gram of hydrogel over 30 days
• Captured 26 mg of CO2 per gram over 400 days in mineral form
• Maintained viability for over one year
• Required only sunlight and artificial seawater to function
• Can be 3D printed into various structures[^1]

The research team demonstrated practical applications by creating:

• A 3-meter high tree-trunk structure at the Venice Architecture Biennale that can bind 18kg of CO2 annually
• Building facade coatings that could capture carbon throughout a building's lifecycle
• Lattice structures that passively transport nutrients through capillary action[^2]

"As a building material, it could help to store CO2 directly in buildings in the future," said Mark Tibbitt, Professor of Macromolecular Engineering at ETH Zurich[^2].

The material represents a low-maintenance, environmentally friendly approach to carbon capture that operates at ambient conditions using atmospheric CO2, contrasting with industrial methods requiring concentrated CO2 sources and controlled conditions[^1].

[^1]: Nature Communications - Dual carbon sequestration with photosynthetic living materials

[^2]: ETH Zurich - A building material that lives and stores carbon