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

摘要

As one of the new methods of materials preparing, interface-regulated mineralization, has been developed and used to fabricate the CaCO3 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 CO2/NH3 bubbles have been substituted for the traditional settled matrix and utilized as new reaction fields of CaCO3. CaCO3 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 CaCO3 in different stages, which allow us to put forward a general kinetic model to reveal the formation mechanism of CaCO3 and implicate a straightforward mean to control the morphology and structure.