A Homochiral Neutral Organic Molecule as Active Ferroelectric for Memtransistor

Abstract Molecular ferroelectrics are of enormous interest due to their ease of synthesis and simplicity in device fabrication. Here, the non‐volatile memory effect in a polycrystalline thin film of the single‐component ferroelectric material naphthalene monoimide (NMI), 6‐bromo‐2‐(1‐phenylethyl)‐1H‐benzo[de]isoquinoline‐1,3(2H)‐dione (NMI‐^RBn), obtained by introducing the enantiomeric α‐methylbenzyl (^RBn) substituents on the NMI backbone is demonstrated. Both NMI‐^RBn and NMI‐^SBn derivatives crystallized in the monoclinic P2₁ space group. The PFM and P‐E hysteresis loop measurements revealed the ferroelectric nature of NMI‐^RBn. Computational studies elucidate a spontaneous polarization mechanism with a calculated polarization of 4.6 µC cm⁻² along the b‐axis. The NMI‐^RBn has subsequently been studied for memtransistor application, where the developed field‐effect transistor (FET) device exhibits gate‐tunable multi‐state non‐volatile rewritable memory states. By varying the gate voltage, the device can be reconfigured to a non‐volatile memory with a tunable memory window of up to 65 V, current modulation between memory states of 10⁴, retention time greater than 20,000 s, and a volatile memory emulating neuronal learning behavior. These findings highlight the potential of homochiral single‐component organic ferroelectrics for applications in ferroelectric FETs and neuromorphic memory devices.