Self-Assembled Naphthalimide Nanoparticles for Nonvolatile ReRAM Devices: An Efficient Approach toward High Performance Solution-Processed and All-Organic Two-Terminal Resistive Memory Devices

For almost a decade, organic nonvolatile memory incorporating an inorganic metal/semiconductor nanoparticles in organic polymers have been well-established in fabricating the resistive switching memory devices. In contrast, for the first time, with an aim to develop all-organic and environmentally friendly memory devices, organic small molecule based nanoparticles have been utilized herein to fabricate a high performance resistive random-access memory (ReRAM) device by incorporating them into a polymer matrix. A naphthalimide based small molecule with formyl and multiple fluorine moieties has been strategically utilized, which enhances the intermolecular H-bonding and subsequently strengthens the intermolecular π–π stacking interaction during nanoaggregate formation. To generate a stable monodispersed nanoparticle with an average diameter of 50 nm, a straightforward yet cost-effective reprecipitation technique has been used. The prepared nanoparticles have been embedded into the poly(vinyl alcohol) polymer matrix to serve as a reliable alternative of the conventional inorganic nanoparticles. The fabricated memory device exhibits an error free memory window with an Ion/Ioff ratio of 103 and a very low write/erase voltage of ±2 V, which are effectively comparable to the existing inorganic nanoparticle based memory devices. In addition, theoretical models employed to study the charge transport of the device suggested that the conduction in the device is ultimately a trap-controlled space charge limited current. Furthermore, the endurance, repeatability test and concentration studies are also thoroughly performed on the device to validate its stability. This simple yet potential approach of incorporating organic nanoparticles into an organic insulator polymer is an easy, greener, and powerful technique to develop an all-organic nonvolatile memory device and could offer a premise for the future development of high-performance low-cost electronic memory devices.