Physikalisches Institut, Westfälische Wilhelms-Universität, Heisenbergstrasse 11, D-48149 Münster, Germany.
J Am Chem Soc. 2012 Sep 19;134(37):15402-9. doi: 10.1021/ja3054018. Epub 2012 Sep 10.
The spectroscopic and electrochemical behavior as well as electrogenerated chemiluminescence (ECL) of a series of donor-π-donor derivatives bearing triphenylamine groups as donor connected to a fluorene, 2,7-bis-(4-(N,N-diphenylamino)phen-1-yl)-9,9'-dimethylfluorene (1), or spirobifluorene core, 2,7-bis-(4-(N,N-diphenylamino)phen-1-yl)-9,9'-spirobifluorene (2) and 2,2',7,7'-tetrakis(4-(N,N-diphenylamino)phen-1-yl)-9,9'-spirobifluorene (3), were investigated. Besides a high photoluminescence (PL) quantum yield in solution (between 81 and 87%), an efficient radical ions annihilation process induces intense greenish blue ECL emission that could be seen with the naked eye. Only the tetrasubstituted spirobifluorene derivative (compound 3) shows weak ECL obtained by a direct annihilation mechanism. Because the energy of the annihilation reaction is higher than the energy required to form the singlet excited state, the S-route could be considered the pathway followed by the ECL process in these molecules. The ECL emissions recorded by direct ion-ion annihilation show two bands compared to the single structureless PL band. The ECL spectra obtained by a coreactant approach using benzoylperoxide as a coreagent show no differences relative to that produced by annihilation, except for an increasing of ECL intensity for all compounds.
一系列含有三苯胺基团作为供体的给体-π-给体衍生物的光谱和电化学行为以及电致化学发光（ECL），供体连接到芴、2,7-双-(4-(N,N-二苯基氨基)苯基)-9,9'-二甲基芴（1）或螺二芴核，2,7-双-(4-(N,N-二苯基氨基)苯基)-9,9'-螺二芴（2）和 2,2',7,7'-四-(4-(N,N-二苯基氨基)苯基)-9,9'-螺二芴（3）进行了研究。除了在溶液中具有高的光致发光（PL）量子产率（在 81%至 87%之间）之外，有效的自由基离子湮灭过程还会引发强烈的绿蓝色 ECL 发射，肉眼可见。只有四取代的螺二芴衍生物（化合物 3）通过直接湮灭机制显示出微弱的 ECL。由于湮灭反应的能量高于形成单重激发态所需的能量，因此可以认为 S-途径是这些分子中 ECL 过程所遵循的途径。通过直接离子-离子湮灭记录的 ECL 发射与单个无结构的 PL 带相比显示出两个带。使用过氧化苯甲酰作为核试剂的核心试剂方法获得的 ECL 光谱与湮灭产生的光谱没有差异，除了所有化合物的 ECL 强度增加。
