Morphology control and mechanisms of CaCO3 crystallization on gas-liquid interfaces of CO2/NH3 bubbles in aqueons-glycine solutions

As one of the new methods of materials preparing, interface-regulated mineralization, has been developed and used to fabricate the CaCO 3 materials with mimetic construction of natural biogenic structures in the present work. Combined with the effect of glycine at different concentrations, novel gas-liquid interfaces of CO 2 /NH 3 bubbles have been substituted for the traditional settled matrix and utilized as new reaction fields of CaCO 3 . CaCO 3 crystals with delicate hierarchical structures and morphologies, such as scallop-shaped, ellipsoidal and spherical structure, have been obtained at the special glycine-mediated gasliquid interfaces. The effect of glycine concentration and the chemical reaction kinetics have been deeply studied. As a result, we have successfully captured in detail the crystallization behaviors of CaCO 3 in different stages, which allow us to put forward a general kinetic model to reveal the formation mechanism of CaCO 3 and implicate a straightforward mean to control the morphology and structure.