Controlled growth and form of precipitating microsculptures

• Published in: Science (American Association for the Advancement of Science) Vol. 355; no. 6332; pp. 1395 - 1399
• Main Authors: Kaplan, C. Nadir, Noorduin, Wim L., Li, Ling, Sadza, Roel, Folkertsma, Laura, Aizenberg, Joanna, Mahadevan, L.
• Format: Journal Article
• Language: English
• Published: United States American Association for the Advancement of Science 31.03.2017; The American Association for the Advancement of Science
• Subjects: Assembly; Carbonates; Coprecipitation; Crystal growth; Crystals; Fabrication; Flowers; Functional materials; Kinetics; Mathematical models; Mineralization; pH effects; Self assembly; Silica; Silicon dioxide
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.aah6350

Controlled self-assembly of three-dimensional shapes holds great potential for fabrication of functional materials. Their practical realization requires a theoretical framework to quantify and guide the dynamic sculpting of the curved structures that often arise in accretive mineralization. Motivated by a variety of bioinspired coprecipitation patterns of carbonate and silica, we develop a geometrical theory for the kinetics of the growth front that leaves behind thin-walled complex structures. Our theory explains the range of previously observed experimental patterns and, in addition, predicts unexplored assembly pathways. This allows us to design a number of functional base shapes of optical microstructures, which we synthesize to demonstrate their light-guiding capabilities. Overall, our framework provides a way to understand and control the growth and form of functional precipitating microsculptures.