Time-Resolved SAXS Study of Colloidal Mg-stabilized Amorphous CaCO3 Precursor for Additive Manufacturing

Calcium carbonate (CaCO3) is the most abundant mineral found in biominerals. Often these biominerals are formed via an amorphous precursor composed of assembly of nanometric particles. These amorphous precursors undergo crystallization in diffusion limited conditions at ambient conditions enabling the formation of intricately shaped single crystals which often maintain the nanometric particle-like microstructure. Inspired by nature, we employ this method in additive manufacturing. Amorphous well-stabilized CaCO3 inks are utilized to form 3D objects which can be further crystalized on demand. Long term stabilization is achieved via the addition of Mg ions as well as some organics. Herein, we aim to study via SAXS the time-resolved formation of these nanoparticles as as a function of Mg concentration in the solution as well as their heat induced size evolution until crystallization takes place.