Phase transformation of calcium carbonate in acetonitrile/H2O mixed solvents: effects of water content and dielectric constant

Abstract

Organic co-solvents are able to tune crystal morphologies and create single-crystal nanocomposites. Here, we used acetonitrile/H₂O binary solvent mixtures with different volume ratios to study the phase transformation of calcium carbonate. We found out that calcium carbonate went through a dissolution recrystallization pathway, or Ostwald ripening process, which largely depends on the content of water and dielectric constant. These findings provide an effective strategy to synthesise biominerals by the use of organic solvents alone.