Dual carbon sequestration with photosynthetic living materials

Natural ecosystems efficiently sequester CO₂ but containing and controlling living systems remains challenging. Here, we engineer a photosynthetic living material for dual CO₂ sequestration that leverages biomass production and insoluble carbonate formation via microbially induced carbonate precipitation (MICP). To achieve this, we immobilize photosynthetic microorganisms within a printable polymeric network. Digital design and fabrication of the living structures ensure sufficient light access and nutrient supply to encapsulated cyanobacteria, enabling long-term culture for over a year. We showcase that photosynthetic living materials are able to sequester 2.2 ± 0.9 mg of CO₂ per gram of hydrogel material over 30 days and 26 ± 7 mg of CO₂ over 400 days. These findings highlight the potential of photosynthetic living materials for scalable, low-maintenance carbon sequestration with applications in carbon-neutral infrastructure and CO₂ mitigation.