Chemically configurable analogue memristors, via the chemiresistive response of oxidized MXene

Abstract

The integration of gas sensing and neuromorphic computing within a single device offers a transformative architecture for artificial olfaction and edge-level intelligent perception. In this study, we demonstrate the feasibility of analogue chemiresistive memristors with an Au/oxidized MXene/Au structure for multifunctional operation. The hydrothermally oxidized MXene, rich in active sites favorable for redox reactions, enables modulation of conductance states via CO₂ and NO₂ gas adsorption on its surface. This dual electrical and molecular tuning yields distinctly separable conductance states, essential for emulating artificial synaptic functions. The device exhibits clear analogue resistive switching and both volatile and non-volatile memory behaviors under electrical and molecular stimuli, indicative of reliable synaptic plasticity. Moreover, gas exposure induces electrical potentiation and depression of conductance states, replicating key features of olfactory synaptic behavior. Its dynamic response to gas pulses, long-term retention, and pulse-dependent plasticity highlight its ability to store and process environmental chemical stimuli in real time. To validate its neuromorphic computing capability, an artificial neural network (ANN) was implemented using the digit-MNIST and fashion-MNIST datasets, achieving recognition accuracies of 95% and 82%, respectively. These results confirm the potential for integrated sensing and computation on a single platform.