Engineering Titanium Dioxide/Titanocene-Polysulfide Interface for Flexible, Optical-Modulated, and Thermal-Tolerant Multilevel Memristor

Multifunctional memristors with a high memory density, low power consumption, flexibility, programmability, and environmental robustness are essential for next-generation memories. In this work, a titanocene-polysulfide complex (Cp2TiS5) with strong S···S interactions and hydrogen bonds was synthesized and integrated with TiO2 to create a novel Cu/TiO2/Cp2TiS5/Ag memristor. This device shows bipolar nonvolatile memory performance with a remarkable ON/OFF ratio (104.8), low switching voltages (VSET, −0.16 V; VRESET, +0.15 V), and low power consumption (2.7 × 10–4 μW). It exhibits multilevel memory behavior, flexibility, optical modulation (VSET decreases from −1.35 to −0.17 V with decreasing irradiation wavelength), and thermal tolerance (up to 200 °C). The electron-rich Cp2TiS5 layer protects the Ag-CFs, while TiO2’s oxygen vacancies and unsaturated Ti atoms interact with sulfur from Cp2TiS5, lowering the Schottky barrier and facilitating charge transport. This work offers promising opportunities in flexible memristive devices for neuromorphic computing under extreme conditions.