Energy-Efficient Fabrication of Biomimetic Materials for Sustainable Infrastructure Applications

Despite significant advances in the synthesis of biomimetic materials, the scalable fabrication of high-performance bulk materials under ambient conditions remains a formidable challenge- particularly when it comes to achieving rapid processing while preserving superior mechanical properties. Herein, inspired by nacre's "brick-and-mortar" structure, this work develops an energy-efficient approach that utilizes ice-templating technology as the structure framework and carbon mineralization for rapid CaCO₃ production, resulting in a strong yet tough carbon mineralized material (CMM) while also fixing CO₂. This material replicates both the hierarchical microstructure and chemical composition of nacre. By precisely controlling the freezing dynamics with dual temperature gradients, this work creates an ordered lamellar skeleton composed of γ-dicalcium silicate (γ-C₂S). The rapid, in situ carbon mineralization under mild conditions generates interspersed CaCO₃ grains within this structure, which are then infiltrated with gelatin to form a nacre-like CMM with exceptional mechanical properties. The resulting material exhibits a flexural strength of 45 MPa (eight times that of a cement-hydrogel composite) and a fracture toughness of 2.03 MJ m^-3 (a 20-fold improvement over unmodified CMM), while maintaining a density of only 1.2 g cm^-3. The enhanced performance stems from multiscale toughening mechanisms, including crack deflection, secondary crack formation, and strong interfacial bonding, all of which facilitate efficient energy dissipation. This work establishes a new paradigm for designing high-performance synthetic materials through the synergistic integration of biomimetic principles with carbon mineralization, offering promising applications in the development of sustainable infrastructure and carbon neutrality.