Ultra-low Cost, Large Area Graphene/MoS2-Based Piezotronic Memristor on Paper: A Systematic Study for Both Direct Current and Alternating Current Inputs

This report is the first demonstration of the fabrication of a two-dimensional (2D) nanohybrid-based, i.e., graphene (Gr)/MoS2, resistive random access memory (RRAM) on paper substrate. Combining graphene with MoS2 on paper helps in improving the overall mobility while still maintaining the dielectric property needed for resistive switching (RS) and ensures a durable, reliable, and repeatable performance due to their high Young moduli. The Gr/MoS2-based paper memory exhibited excellent stable RS behavior, endurance up to 5 × 102 cycles, an ON/OFF ratio of 104 with data retention capacity tested for 104 s. The impedance spectroscopy analysis on the fabricated memristor revealed capacitive behavior which upon application of continuous time signals interestingly exhibited programmability, i.e., resistance variation in the low-frequency regime which disappears at high frequencies. Further, upon bending, due to the piezoelectric nature of the odd layered MoS2, the memristor exhibited lower set and reset values of 3.3 V and −3.3 V, respectively, which could be attributed to the piezotronic effect at the junction of Gr/MoS2. Detailed switching behavior is explained in terms of the conduction bridge mechanism, wherein the Schottky barrier created at the Gr/MoS2 interface helps in the effective movement of the ions. The strategy presented here is a major step ahead in the development of the next generation of papertronic-based, ultralow-cost, disposable memory devices with ease of handling data for security, medical, and Internet of Things (IoT) applications.