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 9

Hydrodynamic diameter measurements of CeO₂ NPs in the presence of HA (5 mg/L) or FA (0.14 mg/L) as a function of time, and NaCl concentration ranging from 0 to 1 mM at pH 8.2, pH 10.2, and pH 12.2: (a) HA, NaCl, and pH 8.2; (b) HA, NaCl, and pH 10.2; (c) HA, NaCl, and pH 12.2; (d) FA, NaCl, and pH 8.2; (e) FA, NaCl, and pH 10.2; and (f) FA, NaCl, and pH 12.2.

(a)

(b)

(c)

(d)

(e)

(f)