Cement and concrete as carbon sinks: Transforming a climate challenge into a carbon storage opportunity

Cement and concrete, while traditionally recognized as one of the main contributors to anthropogenic CO₂ emissions, also have untapped capacity to serve as substantial carbon sinks. This paper provides a comprehensive perspective on how engineered mineral carbonation can transform cement-based materials into carbon storage systems. We briefly review the fundamental mechanisms of CO₂ storage in cementitious systems and highlight current limitations in understanding of reaction kinetics, end-phase regulation and performance control. The effect of CO₂ uptake on material performance is critically evaluated with respect to the fresh performance, mechanical properties and long-term durability. Emphasis is placed on the valorization of alkaline industrial residues and emerging carbonatable binders, which offer sequestration capacity and sustainable resource use. A strategic roadmap is proposed with integration of scientific innovation, regulatory alignment, and carbon accounting in the life cycle, to accelerate the adoption of carbon-storing concrete. This perspective provides a framework to advance cement and concrete as engineered carbon sinks and supports the transition to a climate-positive construction industry.