X-ray diffraction patterns of the ZnO nanorods grown on the ZnO–PVA seed layers (on silicon substrates) annealed at different temperatures, ranging from 250 ◦C to 550 ◦C and are shown in Fig. 5.The X-ray diffraction patterns match the wurtzite hexagonal phase of ZnO. All the peaks correspond to the ZnO phase, except for the two peaks at 44.5◦ and 64.4◦,which are related to the silicon carbide of theXRDsample holder. Fig. 5(a and b) shows the X-ray diffractionpatterns of the ZnO nanorods grown on seeded substrates annealed at 250 ◦C and 350 ◦C, respectively. These patterns reveal that the ZnO nanorods were randomly oriented on the substrates, as seen in the FESEM images (Fig. 6(a and b)). Fig. 5c for sample C exhibits