Hierarchical crystalline organic-inorganic framework enabling high-modulus toughening in nacre.

Crystalline organic-inorganic frameworks in Cristaria plicata nacre achieve near-theoretical modulus and strength, enhancing toughness through a hierarchical structure.

• Why it matters: Improving nanocomposite toughness often compromises stiffness, limiting their structural applications; understanding natural mechanisms can guide better material design.
• What they did: Researchers examined mature nacre's crystalline framework, consisting of aragonite nanorods and biomolecular crystallites, using structural and mechanical analyses.
• The result: The crystalline units enable high modulus and toughness by reducing stress concentrations and allowing synchronized deformation, inspiring reconstituted nacre with both properties.