Effect of Surface Chemistry on Incorporation of Nanoparticles within Calcite Single Crystals

Inclusion of additives into calcite crystals allows one to embed non-native proprieties into the inorganic matrix and obtain new functional materials. Up to now, few parameters have been taken into account to evaluate the efficiency of inclusion of an additive. Taking inspiration from Nature, we grew calcite crystals in the presence of fluorescent silica nanoparticles carrying different functional groups (PluS-X) to investigate the effect of surface chemistry on the inclusion of additives. PluS-X allowed us to keep constant all the particle characteristics, including size and morphology, while changing exposed functional groups and thus zeta potential. The effect on crystal morphology and structure, the loading, and distribution of PluS-X within the crystals have been evaluated with different microscopy and diffractometric techniques. Our data indicate that hydroxyl functionalized particles are entrapped more efficiently inside calcite single crystals without distortion of the crystal structure and inhibition of the growth.