Fig. 3.

Lamellar arrangement in biomaterials. (A) Nacre, as a typical natural material, has a multiscale hierarchical structure. At the molecular level, the interaction of β-chitin and silk protein with 30-nm calcium carbonate particles facilitates the formation of a stable organic–inorganic structure. Reproduced with permission [5]. Copyright 2014, Springer Nature; Reproduced with permission [9]. Copyright 2008, Elsevier; Reproduced with permission [12]. Copyright 2008, Elsevier; Reproduced with permission [83]. Copyright 2011, Elsevier. (B) The conch shell evolves a 3-layer hierarchical lamellar structure to defend itself from the attack of predators. Each of these 3 layers manifests 4 distinct hierarchies at a nano-/microscale. Reproduced with permission [15]. Copyright 2017, Elsevier; Reproduced with permission [14]. Copyright 2013, Elsevier; Reproduced with permission [99]. Copyright 2017, Wiley VCH; Reproduced with permission [100]. Copyright 2003, Royal Society of Chemistry. (C) Euplectella sponge displays optical properties similar to artificial optical fibers while having unique strength and toughness. Moreover, this siliceous sponge confers multiple structural hierarchies from the nanoscale to the macroscale, contributing to its reinforced mechanical properties. Reproduced with permission [112]. Copyright 2005, American Association for the Advancement of Science; Reproduced with permission [113]. Copyright 2007, Elsevier.