Photoinduced Nonvolatile Memory Transistor Based on Lead‐Free Perovskite Incorporating Fused π‐Conjugated Organic Ligands

Abstract

Perovskites field-effect transistors (PeFETs) have been intensively investigated for their application in detector and synapse. However, synapse based on PeFETs is still very difficult to integrate excellent charge carrier transporting ability, photosensitivity, and nonvolatile memory effects into one device, which is very important for developing bionic electronic devices and edge computing. Here, two-dimensional (2D) perovskites are synthesized by incorporating fused π-conjugated pyrene-O-ethyl-ammonium (POE) ligands and a systematic study is conducted to obtain enhanced performance and reliable PeFETs. The optimized (POE)₂ SnI₄ transistors display the hole mobility over 0.3 cm² V^-1 s^-1 , high repeatability, and operational stability. Meanwhile, the derived photo memory devices show remarkable photoresponse, with a switching ratio higher than 10⁵ , high visible light responsivity (>4 × 10⁴ A W^-1 ), and stable storage-erase cycles, as well as competitive retention performance (10⁴ s). The photoinduced memory behavior can be benefiting from the insulating nature of quantum-well in 2D perovskite under dark and its excellent light sensitivity. The excellent photo memory behaviors have been maintained after 40 days in a N₂ atmosphere. Finally, a 2D perovskite-only transistors with a multi-level memory behavior (16 distinct states) is described by controlling incident light pulse. This work provides broader attention toward 2D perovskite and optoelectronic application.