Diatoms in Focus: Chemically Doped Biosilica for Customized Nanomaterials.

Diatoms are photosynthetic microalgae widely diffused around the globe and well adapted to thrive in diverse environments. Their success is closely related to the nanostructured biosilica shell (frustule) that serves as exoskeleton. Said structures have attracted great attention, thanks to their hierarchically ordered network of micro- and nanopores. Frustules display high specific surface, mechanical resistance and photonic properties, useful for the design of functional and complex materials, with applications including sensing, biomedicine, optoelectronics and energy storage and conversion. Current technology allows to alter the chemical composition of extracted frustules with a diverse array of elements, via chemical and biochemical strategies, without compromising their valuable morphology. We started our research on diatoms from the viewpoint of material scientists, envisaging the possibilities of these nanostructured silica shells as a general platform to obtain functional materials for several applications via chemical functionalization. Our first paper in the field was published in ChemPlusChem ten years ago. Ten years later, in this Perspective, we gather the most recent and relevant functional materials derived from diatom biosilica to show the growth and diversification that this field is currently experiencing, and the key role it will play in the near future.