AbstractBi2O3 thin films were prepared with a sol-gel technique, and annealed in air, nitrogen and oxygen. The phase structures of films were analyzed with X-ray diffraction (XRD). Surface morphology was observed with scanning electron microscope (SEM). Electrochromic properties were tested with ultraviolet-visible spectroscopy (UV-Vis) and an electrochemical workstation. It is discovered that the color state of Bi2O3 thin films switched between black and light yellow transparent. The Bi2O3 thin film annealed in nitrogen with 100% stoichiometric phase, higher δ phase, and smaller particle size distribution has the highest electrochromic efficiency of about 21 cm2/C.
Received: 11 January 2017
Published: 26 December 2018