Electrochromic material and electrochromic device based on dynamic metal-ligand complexation

Abstract

The invention belongs to the technical field of electrochromic materials, and discloses an electrochromic material and an electrochromic device based on dynamic metal-ligand complexation. The electrochromic material is formed by mixing metal ions, the electrochromic material and an electrolyte, the electrochromic device is designed based on the dynamic metal-ligand complexation, and the structureof the electrochromic device is divided into a liquid electrochromic device structure and a solid electrochromic device structure. The liquid electrochromic device structurally comprises a first electrode, an electrochromic medium and a second electrode. The solid electrochromic device structurally comprises a first electrode, an electrochromic medium, an ion exchange membrane, an auxiliary mediumand a second electrode. The electrochromic material and the electrochromic device realize adjustable full-visible spectrum and high contrast, and have the advantages of high coloring efficiency, quick electrochromic response, excellent cycle reversibility, ultralow cost and simple preparation process.

Description

technical field [0001] The invention belongs to the technical field of electrochromic materials, in particular to an electrochromic material and an electrochromic device based on dynamic metal-ligand complexation. Background technique [0002] At present, the closest existing technology: the existing electrochromic materials are based on the mechanism of electron transfer, which can be mainly divided into: inorganic oxide electrochromic materials, organic and polymer electrochromic materials, metal-organic ligands Bit-like electrochromic materials. [0003] Inorganic oxide electrochromic materials represented by tungsten trioxide have the characteristics of good stability inherent in inorganic substances and resistance to ultraviolet fatigue. Taking tungsten trioxide as an example, it can achieve a reversible change from colorless to blue under electrical stimulation. Its discoloration mechanism is: when voltage is applied, WO 3 Oxidation / reduction occurs, and at the same...

AI Technical Summary

Problems solved by technology

The advantages of adjustable color can be obtained by modifying the push-withdraw electronic structure on the chromophore, and its coloring efficiency is high, and the contrast is high. Due to the existence of unstable free radicals and redox sites and color-changing sites during the reaction Poor optical memory effect of the colored / faded state due to dots being in the same structural primitive

At the same time, complex synthesis processes are often required, and the cost is relatively high.

The principle of electrochromism of traditional organometallic complexes is based on the redox of the central metal ion, which hinders the electronic transition between the ligand and the metal ion, resulting in a shift in the ligand absorption spectrum and a change in color. The absorption spectrum is generally relatively broad, resulting in low color purity and slow response speed, which also limits its application

[0004] To sum up, the problems existing in the prior art are: the prior art is based on inorganic oxide electrochromic materials with relatively single color, poor cycle reversibility, low coloring efficiency, and low contrast

However, its structural modification is poor, and it is difficult to prepare electrochromic materials with multi-color display.

The complex design and synthesis of organic conjugated polymers in the process of realizing multi-color display materials is also unavoidable, and unstable free radicals are also difficult to eliminate, and the improvement of performance is still limited

Although many research groups have done a lot of research work, they still mainly focus on the modification of original materials, and it is difficult to fundamentally solve the bottleneck encountered by electrochromism. At the same time, progress in the development of new electrochromic mechanisms is slow.

[0006] Significance of solving the above technical problems: By developing a new electrochromic mechanism based on dynamic metal-ligand complexation, using the excellent electrochemical stability of metal ions and the wide selectivity of dye molecular species, the materials are simple and easy to obtain, and the molar absorption spectrum High advantages, overcome the inherent defects of poor color adjustability, low color purity, high preparation cost and poor stability of traditional electrochromic materials, and truly promote the application of electrochromic materials in daily life by improving the performance of electrochromic materials display area of

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