Preparation And Characterization Of Teryidine-based Electrochromic Materials

Nowadays,in addition to metal oxide electrochromic materials,organic electrochromic materials have been got widely studied due to their good structural design ability.Unlike traditional small organic molecules and conjugated conductive polymer electrochromic materials,transition-metal coordination complexes and polymers electrochromic materials show unique advantages in both inorganic and organic electrochromic materials.Different color-converted electrochromic materials can be obtained by designing pyridine ligands of different structures or complexing with different metal ions.In this paper,three small-molecule terpyridine ligands and three polyfunctional triple-pyridine ligands which can be constructed into supramolecules were synthesized by ring formation,Krohnke pyridine synthesis and Suzuki coupling reaction.Proton nuclear magnetic resonance,fluorescence analysis and UV-visible spectroscopy were analyzed on the synthesized materials.The effects of different structures on the performance of the terpyridine ligand were also analyzed.The color change ability of different ligands after complexation with metal ions and the redox performance under cyclic voltammetry were tested.It is proved that aminophenyl substituted terpyridine and three types of terpyridine with large conjugated and telechelic structures can be constructed into supramolecules have good electrochemical redox properties after complexation with metal ions.They are ideal substances as electrochromic materials.Four kinds of metal-ligand supramolecular electrochromic materials were prepared and sprayed into films.The morphology and thermal stability of the materials were tested.The color change of electrochromic materials during electrochemical redox process was studied.Combined with polymethyl methacrylate-lithium perchloratepropylene carbonate gel electrolyte to form an electrochromic device,the change of UV-visible absorbance at different potentials,and finally the potential and color change of the complete oxidation state were studied.The microscopic morphology of the electrochromic thin film and the influence of the electrochemical redox process on the morphology of the electrochromic thin film were also studied.