The presentation demonstrates the acceleration of carbonation kinetics rate in nanostructured interfaces of cementitious systems, crucial for CO2 mineralization in concrete, using 2D carbon-based nanomaterials. Highly exfoliated/nearly monolayered graphene nanoplatelets (GNPs) with 3-5x higher specific surface area than the surface area of cement grains were used. NanoIR mapping on sub-10 nm nanomaterial/C-S-H interfaces of carbonated specimens shown the formation of active sites that generate large quantities of Ca(OH)2 and CaO essential for CO2 mineralization, i.e., CaCO3 formation. A 50-80% higher nanoscale modulus of elasticity and elastic strain energy absorption capability of the carbonated nanostructured interfaces over the material without the GNP reinforcement was demonstrated through quantitative nanomechanical property mapping. Such enhancements in the carbonation kinetics and nanomechanical properties indicate improved CO2 mitigation potential and increased strengthening and toughening/resiliency of carbonated engineered concrete, important performance factors for the material’s serviceability.