在离子液体中的八[8]环薄膜的电化学和电色特性
Takuya Fujimoto1, Michio M Matsushita, Hirofumi Yoshikawa
1Department of Chemistry and Research Center for Materials Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan.
Journal of the American Chemical Society
|November 4, 2008
概括
八度[8]环薄膜在离子液体中显示出显著的电色. 电化学氧化导致颜色变化,由分子中的n-pi过渡解释.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 有机电子 有机电子
背景情况:
- 八[8]环是一种富含硫的宏环化合物,具有潜在的电子应用.
- 离子液体具有独特的电化学稳定性和溶解性能.
- 有机物质中的电染色是由电子结构的氧化还原诱导的变化驱动的.
研究的目的:
- 为了研究八[8]环薄膜的电化学行为.
- 在离子液体中探索八[8]环的电色特性.
- 为了阐明负责观察到的颜色变化的电子转换.
主要方法:
- 八[8]循环烯的薄膜制备.
- 在N,N-二甲基-N-甲基中使用循环电压测量的电化学研究,N,N-二甲基-N-甲基-二甲基-甲基-甲基) 氨基双 (N,N-二甲基-甲基) 三甲基-硫) 胺 (DEME-TFSI) 离子液.
- 光谱分析以将电化学状态与光学特性相关联.
主要成果:
- 八[8]环烯经历一个可逆的两电子氧化.
- 观察到逐步减少,使材料恢复到中性状态.
- 显著的电色表现被证明,在氧化和还原时有明显的颜色变化.
- 颜色的变化归因于氧化后最高占成的分子轨道 (HOMO) 中的洞所启动的n-pi过渡.
结论:
- 八度[8]环薄膜在离子液体中表现出有前途的电色态行为.
- 观察到的电色变化直接与电子结构在氧化还原反应中的变化有关.
- 这项研究突出了八[8]环在电色器件中的应用潜力.
相关概念视频
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Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
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To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
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