Phase and morphology evolution of vaterite crystals in water/ethanol binary solvent

摘要

Keeping stability is important for metastable vaterite to be applied. In this work, crystal evolution of vaterite in water/ethanol binary solvent (WEBS) was investigated. Phase identification was confirmed by XRD measurement. It is found that the stability of vaterite is sensitive to the concentration of surplus CO_3~(2-) and the ethanol mole fraction in WEBS. The vaterite phase would transform to either aragonite or calcite decided by the surplus CO_3~(2-) ions or Ca~(2+) ions, respectively. SEM observation shows that the polymorph evolution also induced the morphology change.