Growth of vertically aligned ZnO nanorods on Teflon as a novel substrate for low-power flexible light sensors

In this work, vertically aligned zinc oxide (ZnO) nanorods were successfully grown by a wet chemical bath deposition method on a ZnO seed-layer-coated Teflon substrate at room temperature. The strong and sharp (0 0 2) peak in the XRD pattern along with the calculated low compressive strain indicated the vertical growth of high-quality crystalline ZnO nanorods along the z -axis on the substrate. The field emission scanning electron microscopy images show the ZnO nanorods to have diameters ranging from 34 to 52 nm. Raman analyses revealed a high E 2 (high) peak at 440.23 nm. A flexible ZnO nanorod-based metal–semiconductor–metal UV detector was fabricated. The device showed a sensitivity of 1466. The responsivity ( R ) of the device is 2.265 A/W, which is 20 times higher than that reported for ZnO-based PDs. Under low power illumination (370 nm, 1.5 mW/cm 2 ), the device showed a relatively fast response and baseline recovery for UV detection. The prototype device shows a simple method for nanorod synthesis and demonstrates the possibility of constructing nanoscale photodetectors for nano-optics applications.