Co₃O₄ mono-dispersed nanoparticle solubility in high-purity water

As more and more nanoparticles are synthesised and applied in industry and society, their safety has started to become an environmental concern. The solubility of Co₃O₄ particles with different morphology and sizes were investigated. The solubility of the mono-dispersed Co ₃O₄ nanoparticle was discovered to be much lower than that of its micrometre counter-partners. A mechanism was proposed to interpret the inconsistency of this finding with the traditional soluble dynamic equilibrium theory. The nanometre particles exist during surface tension interaction because of their small size. The traditional Ostwald-Freundlich relationship cannot apply to nanometre sizes, as it does not include the interface dispersion force interaction.