LAUSR

Abstract We report on the synthesis and characterization of highly monodisperse organically functionalized vanadium oxide (VO x ) nanocrystals with a size of 7–10 nm. We show that how these nanocrystals can be prepared by an improved solvothermal reaction and confirm their composition and structure through various materials characterization techniques. Our results revealed that VO x nanocrystals have a crystalline structure almost identical to that of paramontroseite VO 2 (P) and the majority of vanadium is in oxidation state of V(IV). VO x nanocrystal films can be readily prepared via a spin coating technique. Once thermally annealed at ∼350 °C under an air/N 2 flow, the films exhibited good thermochromic properties (luminous transmittance ( T lum ) ≈49–66%, infrared switching efficiency (Δ T 2000nm ) ≈28–43%, and solar modulating ability (Δ T sol ) ≈7.4–10.7%), corresponding to a phase transition between monoclinic VO 2 (M) and rutile VO 2 (R).