title: Controlling the bio-inspired synthesis of silica.
abstract: The influence of different parameters on the silicification procedure using lysozyme is reported. When polyethoxysiloxane (PEOS), an internally crosslinked silica reservoir, is used, regular structures with a narrow size distribution could be obtained only via introducing the silica precursor in two steps including initial dropping and subsequent addition of residual oil phase in one portion. We found that mixing sequence of mineralizing agents in the presence of a positively charged surfactant plays a key role in terms of silica precipitation when tetraethoxyorthosilicate (TEOS) is the oil phase. In contrast, well-mineralized crumpled features with high specific surface area could be synthesized in the presence of PEOS as a silica precursor polymer, regardless of mixing sequence. Moreover, introducing sodium dodecyl sulfate (SDS) as a negatively charged surfactant resulted in regular silica sphere formation only in combination with hexylene glycol (MPD) as a specific co-solvent. Finally, it is demonstrated that by inclusion of different nanoparticles even more sophisticated hybrid materials can be generated.
authors.affiliation: DWI - Leibniz-Institut für Interaktive Materialien e.V., Lehrstuhl für Makromolekulare Materialien und Oberflächen, RWTH Aachen University, Forckenbeckstr. 50, D-52062 Aachen, Germany.
authors.forename: Tayebeh Mirzaei
authors.initials: TM
authors.lastname: Garakani
authors.affiliation: DWI - Leibniz-Institut für Interaktive Materialien e.V., Lehrstuhl für Makromolekulare Materialien und Oberflächen, RWTH Aachen University, Forckenbeckstr. 50, D-52062 Aachen, Germany.
authors.forename: Marina Juliane
authors.initials: MJ
authors.lastname: Richter
authors.affiliation: Fraunhofer Institute for Applied Polymer Research (IAP), Geiselbergstr. 69, 14476 Potsdam-Golm, Germany; Lehrstuhl für Polymermaterialien und Polymertechnologie, Universität Potsdam, 14476 Potsdam-Golm, Germany. Electronic address: alexander.boeker@iap.fraunhofer.de.
authors.forename: Alexander
authors.initials: A
authors.lastname: Böker
mesh_terms: D000327:Adsorption; D000818:Animals; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry; D060326:Chemistry Techniques, Synthetic / Q000379:methods*; D002645:Chickens; D006018:Glycols / Q000737:chemistry; D009113:Muramidase / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D012822:Silicon Dioxide / Q000138:chemical synthesis*; D012833:Siloxanes / Q000737:chemistry*; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry
chemical_list: D002593:Cetrimonium Compounds; D006018:Glycols; D012833:Siloxanes; D013501:Surface-Active Agents; D012967:Sodium Dodecyl Sulfate; D012822:Silicon Dioxide; D009113:Muramidase; C011480:hexylene glycol; D000077286:Cetrimonium
keywords: High specific surface area; Hybrid materials; Lysozyme; Nanoparticles; Polyethoxysiloxane; Silicification; Surfactant