Colloid Systems and Interfaces Stability of Cerium Oxide Nanoparticles in Aqueous Environments: Effects of pH, Ionic Composition, and Suwanee River Humic and Fulvic Acids

Figure 8

Zeta potential of CeO₂ NPs as function of time in varying concentrations of CaCl₂ ranging from 0 to 1 mM at pH 8.2, pH 10.2, and pH 12.2: (a) 0, 0.05, and 0.1 mM CaCl₂ and pH 8.2; (b) 0.5 and 1 mM CaCl₂ and pH 8.2; (c) 0, 0.05, and 0.1 mM CaCl₂ and pH 10.2; (d) 0.5 and 1 mM CaCl₂ and pH 10.2; (e) 0, 0.05, and 0.1 mM CaCl₂ and pH 12.2; and (f) 0.5 and 1 mM CaCl₂ and pH 12.2.

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