Engineering TiO₂ memristors: A material-centric review

Memristors have emerged as a compact, non-toxic and energy efficient alternative to traditional memory vital for advancing AI-driven fields. Whilst TiO2-based memristors have been extensively researched and reviewed, this study represents a novel approach by deconstructing the material at its core. Through an analytical dissection, the review begins with the fundamental element, TiO2 (powder and thin film forms), and critically investigates its structural, morphological, electrical, and optical properties in relation to its synthesis method, temperature, thickness, bilayers, suboxide phases, electrodes, etc. This aims to critically assess how material properties and processing parameters influence device performance, thereby establishing fundamental guidelines for designing customised memristors. Additionally, the review delves into the latest research on TiO2-based memristors with different hypotheses on switching mechanisms. For the practical realization of tailored memristors, some of the unresolved challenges are identified and outlined to guide future research efforts.