具多變色能力之新穎生質能材料-紫精修飾之呋喃寡聚物於電致變色元件之應用

Abstract

電致變色材料是一種在特定施加電壓下可以反復改變光學性質的物質。這類材料已廣泛應用於我們的日常生活中，例如智能鏡子、智能窗戶和各種可逆變色產品。含有電致變色材料的產品具備屏蔽外界過熱和輻射的能力，並可隨時切換。在近期的研究中，諸如紫精和導電聚合物等有機化合物因其易於調節顏色的特性而引起關注，成為了電致變色應用中最有前景的候選材料之一。 以呋喃為基底的電致色變材料長年在該領域被低估。這不僅是因為它們對光和氧氣的耐久性較低，而且在高氧化電位下不穩定，從而導致聚呋喃的合成困難與較不佳的色變性能。為了解決這個問題，我們實驗室開發了一種名為TriM的寡聚呋喃變色材料。除了其本身的可生物降解特性外, 寡聚呋喃在常溫常壓下相當穩定,而其較低的操作電壓也使得分子結構較不容易被破壞，從而擁有更長的使用壽命。然而，TriM在著色後並不能輕易恢復漂白狀態。為了提升性能，我們通過將寡聚呋喃與聯吡啶共軛，合成了一種名為TriMbpyPF6的新型單取代紫精。TriMbpyPF6不僅具備與TriM相似的特性，更利用作為官能基的聯吡啶得到了較高的褪色能力，並在施加還原電位的過程中了變出了第二種顏色。透過這項改動，TriMbpyPF6在解決TriM問題的基礎上，成為了一種具多變色能力的電致變色材料。

Electrochromic materials alter their optical properties back and forth under specific applied voltages. These kinds of materials have been widely utilized in our daily lives, such as smart mirrors, smart windows, and various color-changing products with reversibility. Those products that contain electrochromic materials possess the ability to shield excess heat and radiation from outside and can switch on and off at any time. In recent studies, organic compounds such as viologens and conducting polymers have aroused attention due to their easy color-tuning properties, which makes them one of the most promising candidates for electrochromic applications. Furan-based materials are undervalued in the electrochromic field due to their low endurance to light and oxygen and their instability under high oxidation potentials, leading to the dismal performance of polyfurans. Therefore, our lab designed an electrochromic oligofuran called TriM. It is biodegradable and stable under ambient conditions and has a lower oxidation potential, resulting in fewer structural defects and longer life cycles. However, TriM exhibits a low bleaching ability after coloration. To circumvent this, we synthesized a novel monosubstituted viologen called TriMbpyPF6 by conjugating the oligofuran with the bipyridine moiety. TriMbpyPF6 shares similar electrochemical properties with TriM, but its bipyridine component not only provides higher decoloration ability but also introduces another color to the oligofuran system during the redox process. Through this modification, TriMbpyPF6 has become a multicolor electrochromic material, further enhancing the solution to the TriM problem.