Enhanced Memristive Performance of Double Perovskite Cs₂ AgBiBr_6-x Cl_x Devices by Chloride Doping

Mixed halide perovskites are promising memristive materials because of their excellent electronic-ionic properties. In this work, lead-free Cs₂ AgBiBr_6-x Cl_x (x=0, 0.2, 0.4, 0.6, 0.8, 1.0) double perovskite films were fabricated using a one-step solution spin-coating method in air. Moreover, the ITO/Cs₂ AgBiBr_6-x Cl_x /Al sandwich-like devices are fabricated to investigate the memristive behaviors. The present memristors exhibit nonvolatile and bipolar resistive switching behaviors without electroforming process. Interestingly, as the chloride content increases, the ON/OFF ratio of the device increases from 10³ to 10⁴ , the average SET voltage and the RESET voltage decrease from -0.40 V to -0.21 V and from 1.55 V to 1.34 V, respectively. In addition, resistance states of devices can be maintained after 100 switching cycles and 10⁴  s of reading. This study provides new possibility for the development of low-power and environmentally friendly memristors.