Influence of the Mixing Ways of Reactants on ZnO Morphology

Figure 4

Variation of the soluble Zn-bearing species with time. Mixing of reactants: (a) adding NaOH to ZnSO₄; (b) adding ZnSO₄ to NaOH. ■: Zn²⁺, ∘: HZnO₂⁻, ▸: ZnO₂²⁻, ☆: ZnOH⁺, ◂: Zn(OH)_2(aq), ▲: Zn(OH)₃⁻, ◊: Zn(OH)₄²⁻.

(a)

(b)