Thermal Activated Synaptic Linearity and Resistive Mechanism in GO–PVA Memristors for High-Stability Organic Neuromorphic Devices

This study presents a temperature-responsive memristive device based on a graphene oxide–poly(vinyl alcohol) (GO–PVA) composite, fabricated using a simple drop-casting and sputtering approach. Incorporating PVA into GO preserves the multilayer structure (6–8 layers) while enhancing film uniformity and mechanical integrity. The Cr/GO–PVA/Cr memristor demonstrates stable analog resistive switching with endurance exceeding 1000 cycles, significantly outperforming pristine GO devices. A comprehensive temperature-dependent analysis reveals a transition in charge transport mechanisms from variable-range hopping (VRH) and space-charge-limited current (SCLC) at low temperatures to Ohmic and Schottky conduction at elevated temperatures due to thermal activation and partial GO reduction. Moreover, synaptic emulation capabilities improve at higher temperatures, particularly in the linearity and precision of potentiation/depression (LTP/LTD) characteristics. These findings highlight GO–PVA composites as promising candidates for thermally stable, energy-efficient, and neuromorphic-memristive systems.