Molecular-Cage Method: An Improvement of the Precipitation Method in Synthesizing Nanoparticles

The molecular-cage method is a convenient and universal way of synthesizing nanoparticles in aqueous phase. In this paper, hydroxyapatite (HA) and zirconium hydroxide nanoparticles are made by the molecular-cage method with a hydroxyl-rich solute. The structure, morphology, and particle size of the product were analyzed by differential scanning calorimetry and scanning electron microscopy. The chemical structures of the particles are not affected by the molecular-cage effect. The sizes of the nanoparticles and the concentration of the solute have a corresponding relationship in a limited range. The higher the concentration of the solute, the smaller the nanoparticles. Besides, HA nanoparticles are also made by the molecular-cage method in a water/ethanol mixture.