电子和孔运输到结合多烯末端的陷组
Sadayuki Asaoka1, Norihiko Takeda, Tomokazu Iyoda
1Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973-5000, USA.
Journal of the American Chemical Society
|August 14, 2008
概括
带有电子或孔陷的末盖聚烯显示了太阳能电池充电传输的前景. 尽管存在一些内部陷,但单链流动性鼓励它们在光伏中使用.
科学领域:
- 有机电子学有机电子学
- 聚合物科学 聚合物科学
- 太阳能光伏发电是如何实现的
背景情况:
- 多化物 (pF) 是一种结合聚合物,在有机电子学中具有潜在的应用.
- 使用特定分子的末端封装可以引入充电捕获站点.
- 了解单个聚合物链中的电荷传输对于设备效率至关重要.
研究的目的:
- 为了合成和表征用电子 ( antraquinone, naphtylimide) 或孔 (di-p-tolylaminophenyl) 陷封顶的多化物.
- 研究单个聚合物链沿线的电荷载体移动性和运输动态.
- 评估这些末盖聚烯在太阳能光伏应用中的潜力.
主要方法:
- 合成具有不同链长 (7-30 nm) 和端盖的多化物.
- 通过脉冲放射溶解将电荷注入聚合物溶液中.
- 监控电荷迁移到端盖陷使用短暂吸收光谱学.
- 分析电荷捕获和衰变动力学.
主要成果:
- 确定了沿着单个链的电子和孔的流动性,发现低于批量测量,但足以用于光伏.
- 电荷的一小部分被困在聚合物链中,通过双分子反应衰变.
- 光谱分析显示了陷位置的电荷转移过渡,这表明电荷重新注入到聚烯骨干中.
结论:
- 末盖聚烯表现出适合单链装置应用的电荷传输特性.
- 该研究强调了端盖对于控制电荷传输和聚烯链中的潜在缺陷的重要性.
- 陷中的电荷转移过渡在这些系统的光物理中发挥着重要作用.
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