High-detectivity perovskite-based photodetector using a Zr-doped TiOx cathode interlayer

Abstract

We investigated the incorporation of Zr into TiO_x cathode interlayers used as hole-blocking layers in an organometallic halide perovskite-based photodetector. The device configuration is ITO/PEDOT:PSS/CH₃NH₃PbI_xCl_3−x/PC₆₀BM/Zr–TiO_x/Al. The use of Zr–TiO_x in the perovskite photodetector reduces the leakage current and improves carrier extraction. The performance of the perovskite photodetector was confirmed by analyzing the current–voltage characteristics, impedance behaviors, and dynamic characteristics. The device with a Zr–TiO_x layer has a high specific detectivity of 1.37 × 10¹³ Jones and a bandwidth of 2.1 MHz at a relatively low reverse bias and light intensity. Therefore, it can be effectively applied to devices such as image and optical sensors.