GLAD synthesized Ag nanoparticles decorated axial n-ZnO/p-CuO heterostructure nanowire arrays for UV photodetector application

Ag nanoparticles (NPs) were decorated on the surface of axial n-ZnO/p-CuO heterostructure (HS) nanowires (NWs) by using a catalytic-free and well-controlled technique called glancing angle deposition (GLAD). A typical high-resolution transmission electron microscope (HR-TEM) image shows formation of an Ag NPs on the surface of axial HS NW consisting of ZnO NW at the top and CuO NW at the bottom. Moreover, the photodetector (PD) based on Ag (NPs)-ZnO/CuO HS NW sample showed a high responsivity ( \({\text{R}}_{\uplambda }\) ${\text{R}}_{\mathrm{\lambda }}$ ) of ~ 118 A/W, specific detectivity ( \({D}^{*}\) $D_{}^{\ast }$ ) of \(\sim 1.38 \times {10}^{12}\) $\sim 1.38\times {10}^{12}$ Jones and noise equivalent power (NEP) as low as \(\sim 2.42 \times {10}^{-12}\) $\sim 2.42\times {10}^{-12}$ W under 365 nm UV illumination. Further, the device showed a low dark current of ~ 5.25 nA at − 1 V applied bias with fast device response of ~ 0.072 s and ~ 1.73 s for rise and fall times respectively. Thus, the fabricated Ag (NPs)-ZnO/CuO HS NWs device can be a suitable applicant for UV photodetector application.