Memristors has been extensively studied as an important candidate device structure for realizing non-Von Neumann computers, neuromorphic and analog computing systems. The conventional memristors are made from transition metal oxides such as TiO_x, TaO_x, WO_x, and HfO_x.¹ The conductance states of such memristors can be adjusted through modulating the distribution of oxygen vacancies in the oxide channels. Recently, memristor-like transport behaviors have been also observed in the electronic devices made from emerging 2D-layered transition metal dichalcogenides (TMDCs, such as MoS₂ and WSe₂).² Such emerging 2D-material-based memristors could be used for constructing novel neural networks with a significantly improved level of connectivity and enabling bio-realistic emulation of brain neuron functions. Therefore, it is highly desirable to further perform nanofabrication and nanoelectronics research to fully explore the applicability and advantage of 2D-TMDC-based memristors for practical neuromorphic applications.

Here, we present a study on the nanofabrication and characterization of memristive devices based on mechanically printed few-layer MoS₂ structures. This work shows that mechanically printed MoS₂ memristors with critical thicknesses exhibit a very low threshold electric field for initiating memristive-switching processes, which is essential for the successful construction and operation of energy-efficient memristor-based neural networks. More importantly, such MoS₂ memristors exhibit both analogue (i.e., gradient) and discrete switching characteristics, which could be further exploited for making reconfigurable memristors for both analog and digital computing applications.

This work leveraged the unique transport properties of 2D layered MoS₂ for memristor-related applications and advanced the scientific/technical knowledge for controlling memristive switching behaviors.