title: Divisive effect of alcohol-water mixed solvents on growth morphology of calcium carbonate crystals.
abstract: Controlling the process of crystal growth is of importance to the biomineralization and materials science. In this work, some novel morphology of calcium carbonate (CaCO3) was precipitated in an ethanol-water binary solvent (EWBS) with a CaCl2/Na2CO3 reaction system. For the solutions of CaCl2/Na2CO3 in EWBS, the alcoholization and hydration of Ca2+ and CO3(2-) were discussed from the radial distribution functions by molecular dynamics simulations, and the number density profiles of water molecules around and approximately 15 A away from CO3(2-) were employed to reveal the distribution of water molecules. It is found that EWBS has a divisive effect on Ca2+ and CO3(2-), and the local inhomogeneity of EWBS would be enhanced by adding some Na2CO3 into it. This inhomogeneity results in an aqueous two-phase system as x E goes up to 0.7. In addition, the novel morphology of CaCO3 under different molar ratios of Ca2+/CO3(2-) and in different mixed solvents were confirmed by XRD and SEM, and the relationships between the morphology of CaCO 3 and the structural properties of mixed solvents were further explored.
authors.affiliation: Department of Chemistry, Zhejiang University, Hangzhou, P. R. China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Lin-Hai
authors.initials: LH
authors.lastname: Yue
authors.forename: Fei
authors.initials: F
authors.lastname: Wang
authors.forename: Qi
authors.initials: Q
authors.lastname: Wang
mesh_terms: D019840:2-Propanol / Q000737:chemistry; D000438:Alcohols / Q000737:chemistry*; D002119:Calcium Carbonate / Q000737:chemistry*; D002122:Calcium Chloride / Q000737:chemistry; D002254:Carbonates / Q000737:chemistry; D003198:Computer Simulation; D003460:Crystallization; D003461:Crystallography; D000431:Ethanol / Q000737:chemistry; D006018:Glycols / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D008958:Models, Molecular; D012997:Solvents / Q000737:chemistry*; D014867:Water / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D000438:Alcohols; D002254:Carbonates; D006018:Glycols; D012997:Solvents; D014867:Water; D000431:Ethanol; C005686:sodium carbonate; D002119:Calcium Carbonate; D002122:Calcium Chloride; D019840:2-Propanol