The effect of changing electrode metal on solution-processed flexible titanium dioxide memristors

TL;DR

This study investigates how different electrode materials, gold and aluminium, influence the resistive switching behavior of flexible solution-processed titanium dioxide memristors, revealing material-dependent device functionalities.

Contribution

It demonstrates that electrode choice critically affects memristor behavior, with aluminium stabilizing and enhancing memristive effects, unlike gold which leads to WORM characteristics.

Findings

Aluminium electrodes promote richer memristive switching behaviors.

Gold electrodes result in WORM resistive devices.

Electrode material influences oxygen ion dynamics and device stability.

Abstract

Flexible solution processed memristors show different behaviour dependent on the choice of electrode material. Use of gold for both electrodes leads to switchable WORM (Write Once Read Many times) resistive devices. Use of aluminium for both electrodes increases the richness of behaviour allowing both curved and triangular memristive switching resistance memories. A comparison device with an aluminium bottom electrode and gold top electrode only exhibited significant memristive resistance switching when the aluminium electrode was the cathode, suggesting that the electrode is acting as a source/sink of oxygen anions. When the gold electrode was the cathode this electrode was deformed by oxygen evolution. These results demonstrate that aluminium is helpful for stabilising and promoting memristive behaviour in sol-gel TiO$_2$ devices and that changing electrodes from aluminium to gold creates fundamentally different device characteristics.