Size- and Interface-Modulated Metal–Insulator Transition in Solution-Synthesized Nanoscale VO₂-TiO₂-VO₂ Heterostructures

The M1 form of vanadium dioxide, which exhibits a reversible insulator–metal transition above room temperature, has been incorporated into nanoscale heterostructures through solution-phase epitaxial growth on the tips of rutile TiO₂ nanorods. Four distinct classes of VO₂-TiO₂-VO₂ nanorod heterostructures are accessible by modulating the growth conditions. Each type of VO₂-TiO₂-VO₂ nanostructure has a different insulator–metal transition temperature that depends on the VO₂ domain sizes and the TiO₂-VO₂ interfacial strain characteristics.