Tuning polymer structures for higher performance multi-level data storage through molecular design

In recent years, designing advanced functional materials that can be used in organic memory devices has become a hot research topic. Among them, polymers have attracted much attention for having at least two stable resistive states. This work reports on the synthesis of various donor-acceptor (D-A) conjugated polymers based on quinoxaline via the Suzuki reaction. ITO/polymer/Al sandwich structure device were prepared with polymer as the active layer through solution spin-coating and Al as electrode by vacuum evaporation method. Among these memory devices, the memory devices based on the polymer (PFQx) synthesized by fluorene as the donor and quinoxaline as the acceptor exhibit excellent binary storage behavior. To further regulate the memory properties, we synthesize conjugated polymers (PFDQx, PFCQx, PFFQx) by modifying quinoxaline with different substituents to act as acceptors, and ternary switching behavior is shown by the memory devices made using these polymers. The PFCQx-based devices have the lowest ternary storage characteristics of V th1 (-0.9 V) and V th2 (-1.3 V) among all the devices, and the greatest switching current ratio of 10 4.6 . All these results indicate the potential application of quinoxaline-based polymers in ternary storage and also provide new ideas for the molecular design of nonvolatile memory materials.