High-detectivity perovskite-based photodetector using a Zr-doped TiOx cathode interlayer†
We investigated the incorporation of Zr into TiOx cathode interlayers used as hole-blocking layers in an organometallic halide perovskite-based photodetector. The device configuration is ITO/PEDOT:PSS/CH3NH3PbIxCl3−x/PC60BM/Zr–TiOx/Al. The use of Zr–TiOx 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–TiOx 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.