聚合物中的聚合物能量格局的表征:富勒烯散体异质连接具有纯和混合相
Sean Sweetnam1, Kenneth R Graham, Guy O Ngongang Ndjawa
1Materials Science and Engineering Department, Stanford University , Stanford, California 94305-4034, United States.
Journal of the American Chemical Society
|September 6, 2014
概括
聚合物太阳能电池 (PSC) 的能量抵消通过增强电荷分离来提高性能. 这项研究量化了来自聚合物形态和分子间相互作用的能量转移,这对于优化PSC效率至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 有机电子 有机电子
- 太阳能光伏发电是如何实现的
背景情况:
- 聚合物中的能量偏移:根据理论,富勒烯散体异质连接可以改善电荷分离并减少聚合物太阳能电池 (PSC) 中的重组.
- 了解这些能量水平差异对于提高PSC性能至关重要.
研究的目的:
- 为了描述聚合物的聚合物相中的孔能量水平:富勒烯散体异质连接.
- 量化不同形态阶段和分子间相互作用产生的能量偏移.
主要方法:
- 循环电压计是循环电压计.
- 吸收光谱法对紫外线的吸收光谱.
- 紫外光电光谱学 (UPS) 是一种超紫外光电光谱技术.
主要成果:
- 在无形和晶体聚合物阶段之间观察到高达150meV的能量偏移,归因于聚合物合长度的变化.
- 由于聚合物:富勒烯分子间相互作用,确定了高达350meV的能量偏移,这是一个经常被忽视的因素.
- 证明分子间相互作用可以诱导一些系统中比形态变化更大的能量转移.
结论:
- 能量水平的变化,特别是来自分子间相互作用的能量水平变化,显著影响PSC的性能.
- 对这些能量水平变化的彻底描述对于全面了解PSC功能和未来设备优化至关重要.
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