A NOVEL HYBRID ROUTE TO CHEMICALLY-TAILORED, THREE-DIMENSIONAL OXIDE NANOSTRUCTURES: THE BASIC (BIOCLASTIC AND SHAPE-PRESERVING INORGANIC CONVERSION) PROCESS

摘要

A novel, hybrid route to chemically-tailored oxide nanostructures with complex, three-dimensional (3D) shapes is introduced: the Bioclastic and Shape-preserving Inorganic Conversion (BaSIC) process. This process couples the massively-parallel and precise replication of biological organisms with rapid, shape-preserving chemical conversion via fluid/solid reactions, so that large numbers (billions) of identical 3D nanostructures can produced with desired (non-natural) compositions. The BASIC process is demonstrated by converting ornate, SiO_2-based diatom frustules (microshells) into MgO nanostructures that retain the frustule shapes and fine features. Such MgO nanostructures are attractive for biomedical and environmental applications (e.g., drug delivery, water purification). By choosing among the numerous shapes and fine features available in bioclastic structures (from diatoms, radiolaria, sponges, silicoflagellates, etc.), and by using other reactive gases, mesoanostructures with a wide variety of shapes, features, and compositions may be mass produced by the BaSIC process.