Diameter-controlled synthesis of ZnO nanorods on Fe-doped ZnO seed layer and enhanced photodetection performance

In this study, we fabricated ZnO nanorods grown on Fe-doped ZnO seed layer by a hydrothermal method. The effects of seed layer on growth of ZnO nanorods and their electrical and photodetection properties were systematically investigated. Results indicate that the average diameter of ZnO nanorods decreases with increasing Fe concentration while the nanorods number density has an increasing trend. The X-ray analysis showed that there is a preferred growth orientation rods in all samples. The electrical resistance of ZnO NRs reduces with increasing of Fe dopant up to 1.5 at.% and then increases with 4.5% Fe in seed layer. Also, the photodetection performance of ZnO nanorod-based photodetectors grown on the Fe-doped seed layer improved as sensitivity increased ∼377 for the sample grown on ZnO seed layer with 4.5 at.% Fe dopant under ultraviolet illumination and the responsivity increased ∼18.6 A/W for sensor including seed layer with 1.5 at.% Fe.