Research Article

Synthesis of Monodisperse Walnut-Like SnO2 Spheres and Their Photocatalytic Performances

Figure 3

SEM images of the SnO2 products prepared with 4 M KOH for (a) 4 h, (b) 6 h, (c) 12 h, and (d) 15 h.
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(b)
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