3rd Physics Institute and Research Center SCoPE, University of Stuttgart, Germany.
Chemphyschem. 2011 Oct 4;12(14):2590-5. doi: 10.1002/cphc.201100442. Epub 2011 Aug 9.
Photoluminescence quenching of single dibenzoterrylene (DBT) dye molecules in a polymeric organic light-emitting diode was utilized to analyze the current dynamics at nanometer resolution. The quenching mechanism of single DBT molecules results from an increase in the triplet-state population induced by charge carrier recombination on individual guest molecules. As a consequence of the long triplet-state relaxation time, its population results in a reduced photoluminescence of the dispersed fluorescent dyes. From the decrease in photoluminescence together with photon correlation measurements, we could quantify the local current density and its time-dependent evolution in the vicinity of the single-molecule probe. This optical technique establishes a non-invasive approach to map the time-resolved current density in organic light-emitting diodes on the nanometer scale.
聚合物有机发光二极管中单二苯并噻吩 (DBT) 染料分子的光致荧光猝灭被用来分析纳米分辨率下的电流动力学。单分子 DBT 的猝灭机制是由于单个客体分子上的电荷载流子复合导致三重态态密度增加。由于长的三重态弛豫时间，其态密度导致分散荧光染料的光致荧光减少。从光致荧光的减少以及光子相关测量，我们可以定量单分子探针附近的局部电流密度及其随时间的演化。这种光学技术为在纳米尺度上绘制有机发光二极管中时间分辨电流密度提供了一种非侵入性的方法。
