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

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