长寿命的电荷分离状态在联体稳定银团中
Matthew Pelton1, Yun Tang, Osman M Bakr
1Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, USA. pelton@anl.gov
Journal of the American Chemical Society
|July 11, 2012
概括
在激光激发后,质稳定的银团显示了光学属性的快速和缓慢衰变. 这些衰变受溶剂极性影响,表明太阳能采集应用的潜力.
科学领域:
- 纳米材料科学 科学 纳米材料科学
- 摄影化学的使用.
- 物理化学 物理化学
背景情况:
- 已经合成了由芳香醇配体稳定的原子单分散银团.
- 这些星团在可见光谱和近红外光谱中表现出强烈的吸收.
研究的目的:
- 在激光激发后,研究这些银星团的依赖时间的光学特性.
- 了解控制它们光学行为的动力过程,并评估它们在太阳能应用中的潜力.
主要方法:
- 超快速激光激发的银星团跨越他们的吸收峰值.
- 时间分辨率光学光谱检测衰变动力学.
- 溶剂极性变化以研究运动过程依赖性.
主要成果:
- 观察到两个不同的动力衰变过程:快速衰变 (<1 ps) 和缓慢衰变 (>300 ns).
- 这两种衰变时间常数都随着溶剂极性增加而减少.
- 这些过程归因于电荷分离状态的形成和再组合.
结论:
- 结合体稳定的银团表现出长期存在的电荷分离状态.
- 它们的广泛光学吸收和长寿命使得它们成为太阳能采集的有希望的产品.
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