Preparation And Properties Of New Electrochromic Materials Based On Ionic Liquids

Energy-saving emission reduction,the development of low-carbon green economy on national energy security,response to global climate change is of great significance.Smart discoloration glass as a green energy-saving glass,is the electrochromic device in the real life of the specific application.Electrochromic devices are now widely used in optical display,signal storage and light regulation.Functional and color conversion of the unity of the obstacles gradually become an important factor in its development,with the wide application of electrochromic devices.The core part of the electrochromic device is electrochromic material,so it is necessary to carry out more new,multi-functional and multi-color conversion of electrochromic materials and electrochromic system research.The research work of this subject is a new type of electrochromic system based on ionic liquid.Through the combination of ionic liquid and one-component liquid crystal and commercial mixed crystal,it solves the problem of long-term single color of polymer dispersed liquid crystal film,and extends its application field and application range.A new type of electrochromic system constructed by ionic liquid combined with silver nanoparticles and silver/gold alloy nanoparticles.The new system has played the advantages of the colorful nature of nanoparticles,and realized the simplification of electrochromic system.The specific research c ontents are as follows:(1)The effects of a series of 1-butyl-3-methylimidazole ionic liquids and bis-trifluoromethyl imide ionic liquids as electrolytes were studied in detail,the [Bmim][Tf2N] has excellent electrochemical stability.The ionic liquid an d diphenylacetylene and biphenyl cyanide liquid electrochromic systems were prepared.The multifunctional polymer dispersion electrochromic liquid crystal system with commercial mixed liquid crystal as the main component was also obtained.(2)Silver nanoparticles with positive charge on the surface are synthesized in situ by ionic liquid,the electrochemical workstations,absorption spectra and transmission electron microscopy were used to study the effect of silver nanoparticles on the surface of the electrode plate.Based on the relationship between the local surface plasmonicity characteristic of silver nanoparticles and the size of silver nanoparticles,by increasing the power-up time,the size of the agglomeration of silver nanoparticles is increasing,and the absorption band of visible light is constantly changing,resulting in the change of the color of the device.At the same time,the optical properties,electrical properties and cyclic stability of silver nanoparticles as electrochromic materials were studied by cyclic voltammetry,visible light transmittance curves and transmission electron microscopy.(3)Based on the in situ synthesis of silver nanoparticles in ionic liquids,silver / gold alloy nanoparticles with positive charge on the surface were synthesized in situ.The color change of silver/gold alloy nanoparticles electrochromic devices was studied by cyclic voltammetry,visible light transmittance curves and transmission electron microscopy(TEM)using the surface plasmonics unique to silver and gold themselves.The electrochromic properties of alloy particles under the same concentration are different from silver nanoparticles,and the alloy nanoparticles have their own unique discoloration properties.At the same time,the unique properties of electrochromic systems such as silver/palladium and silver/gold/palladium and other multi-component nanoparticles in situ synthesis were studied.