在具有光和电场的TiO2表面上翻转分子
Renato N Sampaio1, Guocan Li1, Gerald J Meyer1
1Department of Chemistry , The University of North Carolina at Chapel Hill , Murray Hall 2202B , Chapel Hill , North Carolina 27599-3290 , United States.
Journal of the American Chemical Society
|August 1, 2019
概括
光会导致TiO2上的染料分子反转,然后反转. 这种由电场驱动的分子翻转会影响太阳能电池中的电荷重组.
科学领域:
- 材料科学
- 摄影化学
- 纳米技术
背景情况:
- 染料敏感太阳能电池 (DSSC) 依赖于有效的电子转移从敏感器到半导体氧化物.
- 了解半导体接口上的分子行为对于优化设备性能至关重要.
- 激发状态产生的电场在分子定向中的作用尚未完全理解.
研究的目的:
- 为了研究基敏感剂与TiO2的光诱导的重定向 (翻转).
- 确定这种分子翻转对电荷重组动力学的影响.
- 探索半导体界面上的电场在驱动分子运动中的作用.
主要方法:
- 对酶TiO2纳米晶体进行[Ru(NH3) 5(eina) ](PF6) 2敏感剂的光谱分析.
- 使用脉冲光激发来监测翻转和充电重组的时间解决研究.
- 进行光谱电化学测量,以调查热降低对感应器定向的影响.
主要成果:
- 光激发诱导敏感器翻转和激发状态电子注入.
- 碳酸衍生物或SnO2/TiO2核心/外结构没有翻转.
- 当氧化感应器翻转时,电荷重组速度更快,表明电子合更强.
- 测量了回组合 (26. 7) 和翻转 (0. 12) 的动态同位素效应.
- 热减少启动了翻转,但需要比光激发更高的电场.
结论:
- 在照亮的半导体接口上产生的电场足以重新定位表面固的分子.
- 传感器翻转显著影响充电重组率,影响整体设备效率.
- 这些发现提供了对纳米材料界面电荷转移机制和分子动态的见解.
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