Phase transition study in strongly correlated VO2 based sensing systems

Abstract

Intermediate phase monoclinic M2 was observed by inducing in situ X-ray thermo diffraction on VO2 (M) nanoplatelets. The solid-solid phase transition occurs at around 65 °C assisted with the percolative transition metal-insulator. The existence of an intermediate crystalline phase with room temperature insulator phase and high temperature metallic phase across MIT in VO2 could be of relevance to understand structural contributions to the phase transition dynamics. In addition, pellet of VO2 nanostructures have shown to present good sensing properties to various alcohols vapors at room temperature and good selectivity of methanol with 5.54% sensitivity and limit detection below 5 ppm, compared to isopropanol 3.2% and acetone 2.4% respectively.