Research Article

Facile Synthesis of Rambutan-Like ZnO Hierarchical Hollow Microspheres with Highly Photocatalytic Activity

Figure 4

SEM images of the products prepared with different volumes of ammonia: 0.3 mL (a), 0.5 mL (b), 0.7 mL (c), and 1.2 mL (d).
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(b)
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