Overcoming Efficiency Limitation of Cluster Light-Emitting Diodes with Asymmetrically Functionalized Biphosphine Cu4I4 Cubes
Overcoming Efficiency Limitation of Cluster Light-Emitting Diodes with Asymmetrically Functionalized Biphosphine Cu4I4 Cubes
复制标题
使用不对称功能化双膦 Cu4I4 立方体克服簇状发光二极管的效率限制
DOI：
10.1021/jacs.2c01588
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发表时间：
2022
影响因子：
15
通讯作者：
Hui Xu
中科院分区：
文献类型：
--
作者：
Nan Zhang;Huan Hu;Lei Qu;Ran Huo;Jing Zhang;Chunbo Duan;Yushan Meng;Chunmiao Han;Hui Xu
有望成为新一代团簇发光器件的电致发光(EL)纳米团簇迅速涌现。然而，团簇发射体的慢辐射和严重猝灭在很大程度上限制了器件的性能。在这里，我们报道了两个单官能团化的双膦螯合Cu4I4簇合物[DMACDBFDP]2Cu4I4和[DPACDBFDP]2Cu4I4。吖啶基团的不对称修饰和给电子作用导致团簇以碘-配体电荷转移为主的激发态，具有热激活延迟荧光特征，单线态辐射速率常数显著提高，三线态非辐射速率常数显著降低。因此，与未功能化的母团簇相比，[DPACDBFDP]2Cu4I4获得了16倍的光致发光(81%)和20倍的EL(19.5%)的量子效率，这些新的记录效率使CLED达到了各种EL技术的最先进水平。
Electroluminescent (EL) nanoclusters holding promise for new-generation cluster light-emitting devices (CLEDs) rapidly emerge. However, slow radiation and serious quenching of cluster emitters largely limit the device performance. Herein, we report two monofunctionalized biphosphine chelated Cu4I4clusters [DMACDBFDP]2Cu4I4and [DPACDBFDP]2Cu4I4. The asymmetric modification and electron-donating effect of acridine groups lead to the iodine-to-ligand charge transfer predominant excited states of the clusters, which feature thermally activated delayed fluorescence with markedly improved singlet radiative rate constants and reduced triplet nonradiative rate constants. As consequence, compared to the nonfunctionalized parent cluster, [DPACDBFDP]2Cu4I4achieves 16-fold increased photoluminescence (81%) and 20-fold increased EL (19.5%) quantum efficiencies.Such new-record efficiencies make CLEDs achieve the state-of-the-art performance of all kinds of EL technologies.