Au Nanocrystals Modulate Resistive Switching and Magnetic Properties of Spinel Cobalt Oxide-Based Memory Devices

Interface engineering could significantly modulate the performance of resistive switching memories. Here, Au nanocrystals (NCs) are introduced to decorate the electrode interface of the spinel cobalt oxide (Co₃O₄)-based memory device. Compared to the pure Co₃O₄-based device, the device with Au NCs showed excellent bipolar resistive switching behaviors, uniform initialization voltage, concentrated switching voltage of the Set and Reset processes, reliable cycle-to-cycle switching endurance, and multi-magnetization performance. Based on the analysis of fitting current–voltage (I–V) curves and temperature-dependent resistance, it is demonstrated that Schottky emission conduction and Ohmic conduction are dominated at a high resistance state (HRS) and a low resistance state (LRS), respectively. Improvement in the resistive switching performance can be attributed to the formation of confined oxygen vacancies conductive filaments, where Au NCs create an enhancement of the local electric field, which can efficiently guide the direction of the growth and rupture of conductive filaments. The physical relevancy between resistive switching and multi-magnetization involves in the creation and annihilation of oxygen vacancies, associated with the reversible conversion of the cation valence state (Co²⁺ and Co³⁺). The present study provides a flexible path for enhancing resistive switching and multifunctional electromagnetic device applications.