Nanoparticle-Directed Crystallization of Calcium Carbonate

The crystallization of CaCO3 in the presence of monolayer-protected gold nanoparticles is investigated here. It is found that crystals of CaCO3 grow around the gold nanoparticles, which act as nucleation templates, resulting in metal–organic–inorganic hybrid materials (see Figure). Control of the shape (spherical or needle-like) and polymorph (vaterite or aragonite) is also demonstrated.