Patterned Mineral Films Using the Polymer-Induced Liquid Precursor Process

摘要

The formation of patterned mineral films using benign processing conditions provides a route to materials of interest in the areas of microelectronics, bioMEMS, tissue engineering, and micro/nanocomposites. Calcium carbonate films have been grown on a variety of substrates. While spatial control of the mineralization has been achieved, the morphology of the resulting crystals maintains the equilibrium shape of the particular phase being formed (e.g. rhombohedral crystals in the case of calcite). In contrast, the polymer-induced liquid precursor (PILP) process can be used to create a variety of non-equilibrium morphologies, including thin films of calcite. The PILP process uses micromolar quantities of an anionic polymer to transform the typical solution crystallization process to a liquid precursor process. In the PILP process, liquid-liquid phase separation occurs, resulting in formation of droplets that are highly supersaturated in the mineral ions. These droplets can then deposit on substrates or be molded into various forms, such as films, fibers, and sea urchin replicas.After deposition the droplets first solidify into an amorphous solid, and then crystallize to form non-equilibrium crystal morphologies. In this study, we examine the ability to create patterned calcite films using the PILP process by preferential deposition of the droplets onto self-assembled monolayers.