Conjugated Zwitterion-inspired Flexible Ternary Resistive Memory from Rhodamine Dyes
As one of the candidates for next generation of data storage technique, organic multilevel resistive random access memory (RRAM) has attracted more and more attentions. Even though many types of materials have been fabricated into memory devices and successfully obtained multilevel memory behaviors, they still suffered from complex fabrication processes, relatively expensive price and poor temperature stability, which hindered the further applications of RRAM techniques. On the other hand, many organics dyes with conjugated zwitterion structure are commercially available and inexpensive but rarely considered as memory materials. Herein, two commercially dyes Rhodamine B (Rh B) and Rhodamine 6G (R 6G) were selected as active materials to fabricate memory devices through one-step method. The as-fabricated memory devices showed ternary write-once-read-many-times (WORM) type memory behaviors, with the retention time up to 5000 s. Benefitted from the strong intermolecular interactions, rhodamine-based memory devices could work stably under 80 ºC. Additionally, Rh B and R 6G could also fabricated on various flexible substrates, such as polyethylene terephthalate (PET), stamp and tree leaves. The ternary memory behaviors could sustain after bending for 1000 times. Our work demonstrates the potential of commercially available dyes for low price and easy-fabrication flexible multilevel resistive memories.