In-situ XRD study on phase transition kinetics of vanadium dioxide thin film

Vanadium dioxide (VO 2 ) has great potentials to be used in energy-related fields due to its unique reversible thermochromic metal-insulating properties. In this paper, we used in-situ XRD technique to study the phase transition kinetics of VO 2 thin films, which can change phase from monoclinic VO 2 (M) to tetragonal rutile VO 2 (R). The VO 2 thin films were prepared by a simple solution-based sol-gel method followed by spin coating to achieve the nanoscale thickness on a quartz substrate. During heating, the critical phase transition of VO 2 (M) occurred at 70 °C, which dropped to 45 °C during cooling. A martensite-like crystal phase transformation kinetic model was established based on the Koistinen and Marburger (KM) technique. The relative content of the two phases was quantitatively analyzed using the Rietveld method, and the transformation rate coefficient α was obtained as 0.20345 and 0.12585, for the heating process from VO 2 (M) to VO 2 (R) and the cooling process from VO 2 (R) to VO 2 (M), respectively. This research offers an effective tool for understanding the structural characteristics of thin film VO 2 , paving the way for its future design and applications towards energy-related fields such as in smart windows. • The phase transition of VO 2 varies greatly in different forms of existence. • VO 2 film is prepared using an extremely facile method. • In-situ XRD shows the entire VO 2 film phase transition in detail. • Kinetic model of martensitic-like phase transition of VO 2 thin films is established. • The developed model can be extended and applied to other phase change materials.