Chemical-mechanical dispersing behavior of a nanoceria abrasive

The authors studied dispersing behavior of a nanoceria abrasive under joint actions of mechanical ultra-sonication and chemical dispersants, to explore effective approaches and methods for dispersing it and manifesting its functions of nanometric scale. It was found that mechanical ultra-sonication solely could not disperse the nanoceria abrasive effectively, while dispersants such as sodium hexametaphosphate (SHP) and sodium dodecylbenzenesulfonate (SDBS) could help to disperse the nanoceria abrasive. SHP and SDBS were found to increase value of zeta potential of the nanoceria abrasive markedly and decrease level of apparent viscosity of its slurry observably. It was deduced by analysis that the dispersants increased inter-particles mutual repulsive force by forming steric hindrance between particles and augmenting zeta potential of particle surfaces, which could overcome van der Waals attracting force to some extent, reduce agglomeration and flocculation of the nanoceria particles, thus improve dispersibility and stability of the nanoceria particles in slurries.