Rational Design on Polymorphous Phase Switching in Molybdenum Diselenide-based Memristor Assisted by All-Solid-State Reversible Intercalation Toward Neuromorphic Application

Abstract Synaptic devices based on non-volatile resistive random access memory (RRAM) have inspired increasing opportunities, including in-memory computing and neural engines, while typical filamentary-based RRAM is subjected to large switching current and causes huge power consumptions. In this work, a low-power memristor based on vertically stacked two-dimensional (2D) layered materials, achieved by plasma-assisted vapor reaction, as the switching material, with which the copper and gold metals as electrodes featured by reversible polymorphous phase changes from a conducting 1T-phase to a semiconducting 2H-one once copper cations interacted between vertical lamellar layers and vice versa was demonstrated. Here, molybdenum diselenide (MoSe2) was chosen as the switching material and the reversible polymorphous phase changes activated by the intercalation of Cu cations were confirmed by pseudo-operando Raman scattering, transmission electron microscopy and scanning photoelectron microscopy under high and low resistance states, respectively. The switching can be activated at about ± 1 V with critical currents less than 10 𝜇A with an on/off ratio of approaching 100 after 100 cycles and low power consumption of ~0.1 microwatt as well as linear weight updates controlled by the amount of intercalation. The work opens alternative feasibility of reversible and all-solid-state metal interactions, which benefits monolithic integrations of 2D materials into operative electronic circuits.