[Retracted] Simple Preparation of the CuO•Fe₃O₄/Silica Composite from Rice Husk for Enhancing Fenton-Like Catalytic Degradation of Tartrazine in a Wide pH Range

Figure 3

(a) FE-SEM images of SiO₂, (d–f) FE-SEM images and (g) EDS image of CuO•Fe₃O₄/SiO₂ composite, (h) O elemental map, (i) Cu elemental map, (j) Fe elemental map, and (k) Si elemental map of CuO•Fe₃O₄/SiO₂ composite.

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