Renewable chitin from marine sponge as a thermostable biological template for hydrothermal synthesis of hematite nanospheres using principles of extreme biomimetics

range of uses. Here, chitin-based scaffolds isolated from the skeleton of marine demosponge Aplysina aerophoba were used as a template for the in vitro formation of iron oxide from a saturated iron(III) chloride solution, under hydrothermal conditions (pH~1.5, 90 °C). The resultant chitin-Fe 2 O 3 three dimensional composites, prepared for the first time via hydrothermal synthesis route, were thoroughly characterized using light, fluorescence and scanning electron microscopy; as well as with analytical methods like Raman spectroscopy, electron diffraction and HR-TEM. The results show that this versatile method allows for efficient chitin mineralization with respect to hematite. Additionally, we demonstrate that chitin nanofibers template the nucleation of uniform Fe 2 O 3 nanocrystals.