Preparation And Study Of WO₃-Ag Composite Electrochromic Film

The electrochromic device based on WO3 film has the advantages of relatively rapid response time,good cycle performance,etc.It can be widely used in military camouflage,display manufacturing,green energy-saving construction and so on.With the progress and development of society,the demand for the performances of electrochromic devices has been continuously improved.Therefore,it is necessary to further study WO₃ electrochromic thin films and electrochromic devices to obtain better performances.This article mainly related research work from the following aspects:（1）A new type of electrochromic device assembled process for testing was designed.In this paper,a PVC plate is used to construct an electrolyte tank,which is opened at the edge of the plate as a liquid injection port,and UV curing glue is used for edge sealing.Then,the prepared electrolyte was injected using a syringe and sealed with a UV curing adhesive to complete the assembly of the entire device.The entire process takes place in the glove box.After a period of test and verification,this assembly process solves the existing problems of leakage and bubble generation,and effectively avoids the influence of water and oxygen on the electrochromic reaction process.（2）WO₃ thin films were prepared by RF magnetron sputtering,and the effects of sputtering power on the properties of WO₃ thin films and electrochromic devices were studied.In this paper,we used ITO transparent glass as the substrate,used the magnetron sputtering process to prepare WO₃ film layer,and then assembled it into a device for related testing.The test results show that as the sputtering power increases,the device has better performances in terms of transmittance and transmittance modulation rate in different states.The transparent and colored state transmission of the device sputtered in 190 W 76 T%and 14 T%,respectively,and the modulation amplitude reached 62 T%.However,under the condition of low power sputtering,the best response time,coloring and fading reaction time of the sample sputtered in 100W reached 13.56 s and 2.91 s,respectively,and the cycle stability of the device performance was the highest.（3）The WO₃ thin films were prepared by RF magnetron sputtering.The effects of sputtering gas pressure on the properties of WO₃ thin films and electrochromic devices were studied.The study of the sputtering pressure test group shows that when the sputtering gas pressure is too high or too low,the device shows poor transmittance in the colored state.When the sputtering gas pressure is 1.0 Pa,the optimum transmittance in transparent state and the colored state can be obtained which can reach 75 T%and 16T%,respectively,at a wavelength of 700 nm.For the device’s transmittance modulation amplitude and response time curve of the device,it was found that both parameters increased first and then decreased with the increase of sputtering gas pressure.When the sputtering gas pressure was 1.0 Pa,the higher modulation amplitude of 59%and the bset coloring and fading response times of 13.56 s and 3.11 s were obtained.Cyclic stability tests show that the stabilities of the device performances increase with the sputtering gas pressure first,then decrease,and the best stabilities can be obtained at 1.0Pa.（4）Nano-Ag was used as a modified layer to fabricate WO₃-Ag composite electrochromic film,and the influence of Ag layer on the performance of WO₃ and electrochromic device was studied.We adopted a layered sputtering process to deposit the Ag modified layer and constructed a WO₃-Ag composite electrochromic film.For composite films and devices based on WO₃-Ag assembly,it was found that the response time of the device was greatly reduced after the Ag layer was introduced.The coloring and fading response times were 4.36 s and 2.12 s when the Ag layer sputtering time was6 minutes.At the same time,the cyclic stabilities of various properties have also been significantly improved.However,the introduction of the Ag layer is not conducive to improving the transmittance and the modulation amplitude of the film during the coloring and fading.