Impact of Hydroiodic Acid on Resistive Switching Performance of Lead-Free Cs3Cu2I5 Perovskite Memory

Herein, we employed lead-free Cs3Cu2I5 perovskite films as the functional layers to construct Al/Cs3Cu2I5/ITO memory devices and systematically investigated the impact on the corresponding resistive switching (RS) performance via adding different amounts of hydroiodic acid (HI) in Cs3Cu2I5 precursor solution. The results demonstrated that the crystallinity and morphology of the Cs3Cu2I5 films can be improved and the resistive switching performance can be modulated by adding an appropriate amount of HI. The obtained Cs3Cu2I5 films by adding 5 mu L HI exhibit the fewest lattice defects and flattest surface (RMS = 13.3 nm). Besides, the memory device, utilizing the optimized films, has a low electroforming voltage (1.44 V), a large on/off ratio (similar to 65), and a long retention time (10(4) s). The RS performance impacted by adding HI, providing a scientific strategy for improving the RS performance of iodine halide perovskite-based memories.

Automated summary

Lead-free Cs3Cu2I5 perovskite films were used to construct memory devices with the performance being systematically studied by adding different amounts of hydroiodic acid (HI). Adding an appropriate amount of HI improved the crystallinity and morphology of Cs3Cu2I5 films, leading to enhanced resistive switching performance. This study provides a scientific strategy for improving the resistive switching performance of iodine halide perovskite-based memories.