Enhanced photochromic properties of 1D h-WO₃ embedded in bio-degradable polymer for fabrication of smart windows

Fabrication of h-WO3, a photochromic material is capturing attention of the researchers as it has the ability to modulate solar light transmittance of different wavelengths automatically to adjust the indoor atmosphere. However, maintaining a balance between coloration and bleaching response of such windows have always been a great challenge. In the present paper, an attempt has been made to investigate the coloring/bleaching rates of self supporting, highly flexible h-WO3/Sg-St (Sago-Starch) nanocomposite films fabricated via solution casting technique. The samples were characterized using XRD, FESEM, TEM, Raman and FTIR spectroscopy. XRD reveal the hexagonal structure of WO3 while nano-rod morphology was ascertained using FESEM and TEM. The average diameter of nanorods calculated using TEM comes out to be 41.9 +/- 1.6 nm. The capability of blocking UV region with fast UV irradiation response (<30 sec) and coloration efficiency makes these nanocomposite films a highly acceptable material for smart windows.