Memristors Enabling Biomimetic Pain Perception Based on Pure VO ₂ Nanoplates Synthesized via Annealing of VSe ₂ Nanoplates

Monoclinic vanadium dioxide (VO 2 (M)) has garnered significant attention due to its metal–insulator transition (MIT) and application potential in Mott transistors and memristive devices. Nevertheless, synthesizing stoichiometric VO 2 remains challenging due to the redox instability of V 4+ in VO 2, which readily oxidizes to V 5+ or reduces to V 3+ . Here, we present an attractive approach for synthesizing high-purity VO 2 by thermally oxidizing two-dimensional (2D) vanadium diselenide (VSe 2 ) nanoplates. Comprehensive characterization via Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning transmission electron microscopy (STEM) confirms the formation of M1-phase VO 2 with a well-defined stoichiometric ratio. The resulting VO 2 nanoplates present pronounced threshold switching (TS) behavior, enabling the fabrication of robust Au/VO 2 /Au memristors with exceptional stability over 3,100 cycles and a switching ratio of up to 320. The devices exhibit rapid switching characteristics, achieving an on-state transition in 30 μs and off-state recovery in 20 μs, highlighting their potential for high-speed memory applications. This memristor emulates nociceptive behaviors, such as threshold detection, relaxation, and sensitization. This work provides a scalable synthesis route for VO 2 nanoplates and highlights their functionality in mimicking bioinspired neuromorphic systems, paving the way for next-generation sensory applications.