High-detectivity perovskite-based photodetector using a Zr-doped TiO_xcathode interlayer

Abstract

We investigated the incorporation of Zr into TiO _<i>x</i> cathode interlayers used as hole-blocking layers in an organometallic halide perovskite-based photodetector. The device configuration is ITO/PEDOT:PSS/CH₃NH₃PbI _<i>x</i> Cl_3-<i>x</i> /PC₆₀BM/Zr-TiO _<i>x</i> /Al. The use of Zr-TiO _<i>x</i> 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 _<i>x</i> 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.