Institute of Physics, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands.
Chemphyschem. 2012 Mar;13(4):946-51. doi: 10.1002/cphc.201100788. Epub 2011 Dec 19.
Organic nanoparticles made of a push-pull triarylamine dye with an average diameter of 60 nm, were prepared by reprecipitation. We study their photophysical properties by a combination of photothermal and fluorescence microscopy. Photothermal contrast provides a quantitative measure of the number of absorbers. The size of nanoparticles estimated from the absorption measurements was compared with sizes measured by AFM. Fluorescence and absorption microscopy provide quantum yield on the single-particle level as a function of excitation intensity. The quantum yield strongly decreases at high intensities because of singlet-singlet or singlet-triplet annihilation. We also report the formation of molecular thin layers and of labyrinth-shaped structures on glass substrates, presumably induced by dewetting.
通过再沉淀法制备了平均直径为 60nm 的推挽三苯胺染料的有机纳米粒子。我们通过光热和荧光显微镜的组合研究了它们的光物理性质。光热对比为吸收体的数量提供了定量的衡量标准。通过吸收测量估计的纳米粒子的大小与 AFM 测量的大小进行了比较。荧光和吸收显微镜提供了作为激发强度函数的单粒子量子产率。由于单重态-单重态或单重态-三重态湮灭，量子产率在高强度下急剧下降。我们还报告了在玻璃衬底上形成的分子薄层和迷宫状结构，这可能是由去湿引起的。
