VO₂ for Sensing and Energy Storage

Featuring a thermally driven metal-insulator phase transition (MIT) at 67^oC, VO₂ finds potential applications in electronics, optics and thermal management. In our recent efforts, we discovered that the surface conduction of VO₂ is highly sensitive to immersion to aqueous solution of salts. Based on this effect, we develop a high-speed, ion-selective, in-memory sensor that operates without the need for external voltage by leveraging the built-in electric fields in the Helmholtz layer at the VO₂-liquid interface. The in-memory sensor, or memsensor, mimics the neuroplasticity in chemosensory neurons of the model organism Caenorhabditis elegans, and guides a miniature boat to simulate the latter’s adaptive chemotaxis in food search. In another application, we exploit the latent heat of the MIT in VO₂ to manage thermal energy dissipation in microelectronics.