Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah 84112, USA.
Phys Rev Lett. 2009 Oct 16;103(16):167401. doi: 10.1103/PhysRevLett.103.167401. Epub 2009 Oct 12.
The distribution of chromophores in single polymer chains is revealed by photoluminescence excitation spectroscopy under excitation of the backbone and detection of emission from an end cap. Spectral broadening in excitation exceeds that in emission. An increase in vibronic coupling for shorter (higher energy) chromophores is resolved, leading to intrinsic spectral broadening and making higher energy units more effective donors. The results suggest routes to increasing absorption breadth while minimizing disorder as required for efficient photovoltaics.
通过在激发主链并检测端帽发射的情况下进行光致发光激发光谱学，可以揭示单个聚合物链中发色团的分布。激发时的光谱展宽超过发射时的光谱展宽。解决了较短（较高能量）发色团的振子耦合增加的问题，导致固有光谱展宽，使较高能量单元成为更有效的供体。结果表明，在满足高效光伏器件所需的最小无序的情况下，增加吸收带宽的途径。
