Abstract
Reversible photochromic hybrid organic–inorganic films containing nanocrystalline cellulose as a matrix and tungsten oxide as a photochromic component (CNC/WO
3
) were obtained via a simple and quick solvent casting method. The films were studied by scanning electron microscopy, together with element mapping, FT-IR spectroscopy and X-ray diffraction, confirming successful incorporation of WO
3
nanoparticles into a nanocellulose matrix. Thermal analysis data indicated that the modification of a nanocellulose matrix with WO
3
increases its thermal stability. The CNC/WO
3
films showed a quick coloration-bleaching transition with good reversibility within 20 min, without notable degradation of photochromic properties after 10 cycles. The synthetic method proposed allows for scalable preparation of highly efficient low-cost WO
3
-based photochromic materials.
Graphic abstract