Preparation And Performance Research Of All Solid Stateelectrochromic Device

With the development of science and technology,energy crisis,environmental pollution and global warming were problems that have been plaguing the world for a long time.However,color-changing materials have been researched based on their advantages of energy conservation and non-pollution.Among them,the electrochromic material refers to its reversible change in color or transparency on the macroscopic level under the action of external electric fields such as positive and negative or high and low,that is,the change of optical properties such as the transmittance or reflectance of the material.The assembled devices by electrochromic materials were called electrochromic devices,which were practically applied in the fields of automotive anti-glare rearview mirrors,intelligent energy-saving windows,and low-energy display devices.This paper was based on the preparation of all-solid-state electrochromic devices.The preparation and properties of nickel oxide films and tungsten oxide films were studied.The main research contents and conclusions are as follows:1.The monodispersed NiO nanoparticles were successfully prepared by rapid thermal injection method,and the effects of oleic acid content and reaction temperature on the nanoparticles were investigated.In addition,the formation mechanism of NiO nanoparticles were also analyzed.The transmission electron microscope（TEM）characterization shows that the synthesized NiO nanoparticles are uniform in size and have good uniformity and monodispersity.The size and optical bandgap energy of NiO nanoparticles can be controlled by changing the reaction temperature.2.NiO electrochromic thin films were successfully prepared on ITO glass by simple mechanical mixing and pulling coating methods.It has been found that the electrochromic properties of NiO films are general,and its optical modulation range is20.6%.The reason for the analysis may be that the thickness of the films is too low.Changing the number of coating films or the annealing temperature can regulate the electrochromic properties of the films.3.The WO₃ thin film with homogeneous surface were prepared by the potentiostatic and potentiodynamic electrodeposition method.The thin film by the potentiodynamic electrodeposition has excellent electrochromic properties.In the potentiodynamic electrodeposition mode,the size of the particles is larger than that of deposited by potentiostatic.The deposition is not continuous in a voltage range,and there is an interruption between each cycle,which is different from the potentiostatic deposition.4.A NiO/WO₃ complementary electrochromic device was assembled.The device consists of two transparent ITO conductive layers,an ion storage layer（NiO）,a WO₃electrochromic layer,and an electrolyte layer（1M LiClO₄+PC+PMMA）.Comparing the performance of the test devices,the device has a better optical modulation amplitude（56.8%）and faster response time（colored/bleached time=7.2 s/8.9 s）.