Cross‐Bar SnO2‐NiO Nanofiber‐Array‐Based Transparent Photodetectors with High Detectivity

Abstract An cross‐bar structure is employed to design a transparent p ‐ n junction‐based photodetector. The device consisting of aligned n ‐SnO 2 and p ‐NiO nanofibers is prepared via a mature electrospinning process that is suitable for commercial applications. It exhibits a high detectivity of 2.33 × 10 13 Jones under 250 nm illumination at −5 V, outperforming most state‐of‐art SnO 2 ‐based UV photodetectors. It is also endowed with a self‐powered feature due to a photovoltaic effect from the p ‐ n junction, resulting in a photocurrent of 10 −10 A, responsivity of 30.29 mA W −1 at 0 V bias, and detectivity of 2.24 × 10 11 Jones at 0.05 V bias. Moreover, the device is highly transparent (over 90% toward visible light) due to the wide band gap of photoactive materials and well‐designed cross‐bar fiber structure. Additionally, an n‐SnO 2 ‐p‐ZnO:Ag (Ag doped ZnO) self‐powered UV photodetector is fabricated that shows good performance and give another example of the use of the cross‐bar structure.