The effects of MCNTs on electro-spinning carbonization microstructure of polyimide composite film and resistive switching behavior

Abstract Polymer matrix electronic memory devices exhibit many advantages, such as simple structure, good scalability, high mechanical flexibility, and low fabrication cost. In this paper, polyimide nanofibers and composite nanofibers combined by multi-walled carbon nanotubes (MCNTs) were prepared using electro-spinning method, and carbonized to obtain carbon nanofibers (SC-PI) and carbon composite nanofibers (SC-MCNTs). Based on in-situ polymerization method, two novel polyimide composite memory devices were fabricated using composite polyimides doped with those carbon nanofibers. The TEM and SAXS test results confirm that the MCNTs combined into the carbon nanofibers introduces two transition zones (TZs) locating between MCNTs and carbon nanofibers and between carbon nanofibers and PI matrix, resulting in a special multilevel resistive switching behavior of the SC-MCNTs/PI memory device different from the SC-PI/PI memory device, with a high ON/OFF current ratio about 10 3 –10 4 and an excellent retention > 3000 s. Based on the TZs distribution of the composites, different physical models are proposed to explain the charge transmission mechanism of the resistive switching behaviors. The studies on the effects of the MCNTs on carbon composite microstructures relative to the multilevel resistive switching are possible to further improve the performance of polymer-based memory devices.