Tungsten-Doped VO2/Starch Derivative Hybrid Nanothermochromic Hydrogel for Smart Window

Abstract

Highly efficient energy-saving windows with high solar modulation properties (ΔTsol) are the everlasting pursuit of research for industrial applications in the smart window field. Hybridization is an effective means of improving both ΔTsol and luminous transmittance (Tlum). In this paper, hybrid thermochromic films were synthesized using tungsten-doped VO2 nanoparticles (NPs) and starch derivatives. Thermoresponsive 2-hydroxy-3-butoxypropyl starch (HBPS) was prepared with a low critical solution temperature (LCST) varying from 32 to 21 °C by the substitution of reactive groups. The hybrid film was obtained by dispersing W-doped VO2 NPs in HBPS hydrogels, which exhibiting remarkable solar modulation property (ΔTsol = 34.3%) with a high average luminous transmittance (Tlum, average = 53.9%).