Coexistent VO2 (M) and VO2 (B) Polymorphous Thin Films with Multiphase-Driven Insulator–Metal Transition

Abstract

Reversible insulator–metal transition (IMT) and structure phase change in vanadium dioxide (VO2) remain vital and challenging with complex polymorphs. It is always essential to understand the polymorphs that coexist in desired VO2 materials and their IMT behaviors. Different electrical properties and lattice alignments in VO2 (M) and VO2 (B) phases have enabled the creation of versatile functional devices. Here, we present polymorphous VO2 thin films with coexistent VO2 (M) and VO2 (B) phases and phase-dependent IMT behaviors. The presence of VO2 (B) phases may induce lattice distortions in VO2 (M). The plane spacing of (011)M in the VO2 (M) phase becomes widened, and the V-V and V-O vibrations shift when more VO2 (B) phase exists in the VO2 (M) matrix. Significantly, the coexisting VO2 (B) phases promote the IMT temperature of the polymorphous VO2 thin films. We expect that such coexistent polymorphs and IMT variations would help us to understand the microstructures and IMT in the desired VO2 materials and contribute to advanced electronic transistors and optoelectronic devices.

LiV3O8 and Graphene Oxide Nanocomposite as a Cathode in Lithium-Ion Batteries

“…It can be seen that VO 2 is well assigned to the VO 2 (B) phase (JCPDS: 81−2392). 29,30 N1-Precursor can also be basically attributed to the VO 2 (B) phase, which manifests that its main component is VO 2 . Nevertheless, the background noise of N1-Precursor is significant, which may be due to the existence of the oxygencontaining lithium source within N1-Precursor.…”