Morphology Control in the Synthesis of CaCO₃ Microspheres with a Novel CO₂Storage Material.

A green and template-free method was applied to control the morphology of CaCO3 microspheres with a layered nanostructure surface and pure crystalline phase of vaterite via the hydrothermal reaction between Ca(OH)2 saturated limpid solution and a novel CO2-storage material (CO2SM). Morphologies of the as-prepared CaCO3 crystals could be tuned with CO2SM concentration, reaction temperature, or crystallization time. After the precipitation of CaCO3 crystals, the filtered solution could not only be used to absorb CO2 but also to produce CaCO3 microspheres repeatedly with the addition of Ca(OH)2 solution. Furthermore, an aggregation and self-assembly mechanism for the formation CaCO3 microspheres had been proposed. As a result, this novel synthesis strategy of CaCO3 microspheres with CO2SM again emphasized that was possible to synthesize inorganic/organic hybrid materials with exquisite morphology and offered an alternative way for comprehensive utilization of CO2.