Functionalization of Diatom Biosilica and Morphologically Controlled Mineralization of Porous Hybrid Materials

• Applicants: Professor Dr. Eike Brunner; Professor Dr. Stefan Kaskel
• Subject Area: Solid State and Surface Chemistry, Material Synthesis ; Synthesis and Properties of Functional Materials
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 516450547

The present project aims to develop methods for the (regioselective) functionalization of diatoms with microporous materials such as zeolites and metal-organic frameworks (MOFs). Regioselectivity could be achieved for example by exploitation and/or introduction of local differences in chemical composition (organic, inorganic) of diatom biosilica. Functionalization with microporous materials will create hierarchical pore systems which are expected to show improved mass transport characteristics in catalysis and adsorption kinetics. A joint effort of the two applicant groups with complementary expertise is essential for this project. Engineering of silica biogenesis will be performed in vivo by modification of cultivation conditions as well as in vitro modifications. For example, it is planned to insert “foreign” elements such as Al and Zn into the biosilica and to analyze their spatial distribution. Given the morphological differences between different cell wall regions (e.g., valves vs. girdle bands), functionalization will also be tried in a regioselective manner. The planned work is focused to address the following questions: How can variations in chemical composition be introduced into diatom biosilica and exploited for hybrid materials design? How can (regioselective) variations in the composition of modified biosilica be used to hybridize it with microporous materials? What are structural, catalytic, and physisorption properties of biosilica-based porous hybrid materials?

• DFG Programme: Research Grants