Thanks to their complex hierarchical designs, natural materials achieve extraordinary mechanical properties going beyond the properties of their single constituents. In such designs, a first hierarchical structure is formed by nanosized elements glued together by biopolymers, which act as a building element for more complex microarchitectures. On such a base, a new method to produce 3D nature-inspired bulk materials with enhanced mechanical properties has been developed . The uniqueness of such materials lies in the large-range supercrystalline organo-functionalized iron oxide structures that are obtained. Thus, in order to tune the final properties, it is mandatory to understand how both the self-assembly process and the nature of the building blocks affect the final material. Thanks to the combination of Electron Microscopy, Small Angle X-Ray Scattering, Small Angle Neutron Scattering, Synchrotron Micro-Computed Tomography, and Micromechanical testing, we are now able to relate the formation, evolution and morphology of the supercrystalline domains to the final mechanical response. For instance, it has emerged that different self-assembly methods lead to dramatically different supercrystallinity, and thus, different mechanical properties. Furthermore, changing the organic functionalization (type and amount) of the ceramic nanoparticles has also appeared to play a crucial role in the supercrystals’ final morphology and properties. Such understanding can be used to establish the key synthetic parameters guiding the obtainment of bio-inspired ceramic-based nanocomposites with improved final properties.
 G.A. Schneider et al., Nat Mater 15, 2016