Preparation And Electrochromic Properties Of Vanadium Pentoxide Film

Panzhihua-xichang area in Sichuan province is famous for its vast vanadium resource. In this thesis, V₂O₅ films were prepared by improved Sol-Gel method, in which the V₂O₅ crystal produced by Panzhihua Iron&Steel Corporation was used as the raw materials. The effects of technical parameters on the micro-structures and surface morphology and the electrochromic properties were mainly explored.The optimized technical parameters of preparing V₂O₅ gel are 800～900℃of melting temperature, 5～20min of annealing time. The optimized gel mucosity is 1.0～3.0 Pa·S. For the V₂O₅ films with the thckness about 0.5～40μm prepared by spinning, the optimized spinning rate is 400～600r/min, 20～40s of spinning time. Morever, the V₂O₅ films with the thckness about 0.5～40μm prepared by dipping, the optimized dipping rate is 1.5～3.0mm/s.The resistivity of the V₂O₅ films is decreased with the increase of annealing temperature, and the resistivity of the annealing films is higher than that of air drying films. With the increase of film thckness, the resistivity of the V₂O₅ films is decreased. For the short wave light of 360～420nm wavelength, the V₂O₅ films possesses higher absorptivity, higher transimission for the light wave bigger than 550nm. However, for visiable light with wavelength bigger than 620nm, V₂O₅ films possesses lower transimission. With the increase of V₂O₅ film thickness, the transimission is decreased. V₂O₅ films possesses anode and cathode electrochromic properties, anode electrochromics for proximal ultraviolet wave, cathode electrochromics for the wave of wavelength bigger than 500nm. With the increase of V₂O₅ film thickness, the electrochromic efficiency is improved.