At present, electrochromic material mainly applied in dimming rearview mirror, energy-efficient windows, electrochromic glasses, camouflage military equipment, electrochromic displays, and other fields, with the broad application prospects. Study has indicated that, all-solid electrochromic film device has a wide range of potential application in smart window (such as automotive, construction and utilization of solar energy, etc.), in recent years, and thus, electrochromic phenomenon has caused a lot of attention to research institutions again.

 

All-solid electrochromic film device in accordance with the transmission cationic type can be divided into the two categories of H+ type and Li+ type, where in device of Li+ type has the advantages of independent surroundings, good memory effect and stability, and being the focus of solid-state device research and development. This article presents new electrochromic film lithiated method - electron beam heating evaporation metal Li, and study on the chemical, electrochemical and physical properties of different degree lithiated of tungsten trioxide film, and found that at the preparation conditions of a substrate temperature of 60 to 100°C, oxygen partial pressure of 2.0*10-2Pa, at a deposition rate of 1~1.5nm/s, the obtained WO₃ films shows amorphous, with the best electrochromic properties.

 

The reaction of lithiated WO₃ electrochromic film is reversible, which is to say, under the effect of faded voltage, lithium in the lithiated film can be double extracted in both forms of ion and electron. The lithiated degree is related to the chemical composition of film. When lesser degree of lithium, tungsten bronze is formed in the film with lithium injection, WO₃ film turns from colorless to blue; with the larger amount of lithium injection, color effect becomes more obvious, and with the well reversibility. In addition, this electron beam heating evaporation of lithium metal Li dry tungsten trioxide films is without introducing unwanted impurities, and also the degree of vulnerability of lithium is easy to be control; further, the generated electrochromic film has the properties of excellent reversibility and optical adjustment.