Assembly Synthesis of Sheet-like Calcite Array and Stable- Vaterite by Supported Liquid Membrane

CaCO3 can crystallize as calcite, aragonite and vaterite. Calcite and aragonite are the most common biologically formed CaCO3 polymorphs, and vaterite is transformed into calcite via a solvent mediated process. Calcium carbonate makes an attractive model mineral for studies, since the morphology of CaCO3 has been the subject to control in biomineralization processes. And control of vaterite also has significance for various purposes because it has some features such as high specific surface area, high solubility, high dispersion, and small specific gravity compared with the other two crystal phases. Therefore the polymorph and morphology control of CaCO3 has been intensively investigated in recent years. Double-hydrophilic block copolymers, the protein macromolecules and Au nano-colloids have been used as additives for the crystallization of CaCO3. In addition, Langmuir monolayer, foam lamellac, polymer substrates and crystal-imprinted polymer surfaces have been used as templates for the polymorph and morphology control of CaCO3 crystals. However, there was no research simulating the transport way of bio-membrane to control the morphology of CaCO3, and furthermore assembled sheet-like calcite array has not been reported. Here we described a novel biomimetic strategy for the assembling synthesis of sheet-like calcite array and stable vaterite by supported liquid membrane (SLM) containing mobile carrier with different concentration.