Understanding the Origin and Evolution of Resistive Effects during Switching Action in MAPbBr₃ Single Crystals

Metal halide perovskite single crystals (MHPSCs) have garnered significant attention due to their exceptional optical and electrical properties, making them promising candidates for applications in solar cells and photodetectors. The single-crystal form of these materials exhibits superior characteristics compared to their polycrystalline counterparts. However, despite considerable efforts to understand hysteresis, there is still limited knowledge about the underlying mechanisms driving resistance changes in MHPSCs under external stimuli, such as scan rate and bias. This article presents a comprehensive investigation into the origin and evolution of resistive effects in the switching behavior of MAPbBr3 single crystals. Our aim is to fill these gaps in understanding and provide valuable insights for the development of memristor devices. To observe and interpret the switching behavior, we employ various characterization techniques, including current–voltage (J–V) measurements, current–time (I–T) measurements, and electrochemical impedance spectroscopy (EIS) measurements under different scan rates and bias levels. Our findings suggest that during switching, the single crystals (SCs) exhibit high resistance at low applied bias, whereas higher applied bias results in a lower resistance value. We attribute the stable switching response at lower bias to the lower concentration of accumulated ions and electronic charge carriers. Conversely, an excess of charge accumulation at high bias leads to transient or decay responses in the I–T measurements. By gaining a deeper understanding of resistive effects in MHPSCs, this study contributes to the design and optimization of MHPSC-based devices, particularly in the context of halide-based perovskite memory devices. The insights gained from this research pave the way for the enhanced performance and improved reliability of perovskite memory devices, bringing us closer to realizing their full potential in various electronic applications.