Two-dimensional perovskite PrNb₂O₇ for multifunctional electronic and optoelectronic devices

Two-dimensional (2D) perovskite oxides have garnered significant interest owing to their potential applications in multifunctional electronic and optoelectronic devices. In our work, the engineering of 2D perovskite PrNb₂O₇ (PNO) is explored to advance multifunctional electronic and optoelectronic applications. The PNO nanosheets are prepared using a two-step method, which involved solid-phase calcination for precursor synthesis and subsequent liquid-phase exfoliation. PNO nanosheets exhibit a high dielectric constant (21.6), enabling their use as gate dielectrics in semiconducting single-walled carbon nanotubes (s-SWCNTs) transistors. The resulting devices demonstrate a high on/off ratio of 1 × 10⁶ at a low operating voltage of 5 V. Furthermore, individual PNO nanosheets photodetectors show outstanding performance under 280 nm ultraviolet irradiation at 3 V, featuring a high responsivity of 66.7 AW^-1 and a specific detectivity of 3.4 × 10¹² Jones. Additionally, PNO nanosheets devices successfully emulate light-induced synaptic behaviors, including "learning-forgetting-relearning" dynamics. This work not only establishes PNO as promising candidate material for 2D electronic and optoelectronic devices, but also paves the way toward future integrated devices for sensing, memory, and neuromorphic computing.