CF3 Substitution of [Cu(P^P)(bpy)][PF6 ] Complexes: Effects on Photophysical Properties and Light-Emitting Electrochemical Cell Performance.,ChemPlusChem

当前位置： X-MOL 学术 › ChemPlusChem › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

CF3 Substitution of [Cu(P^P)(bpy)][PF6 ] Complexes: Effects on Photophysical Properties and Light-Emitting Electrochemical Cell Performance.
ChemPlusChem ( IF 3.0 ) Pub Date : 2018-02-05 , DOI: 10.1002/cplu.201700501
Sarah Keller ₁ , Fabian Brunner ₁ , José M Junquera-Hernández ₂ , Antonio Pertegás ₂ , Maria-Grazia La-Placa ₂ , Alessandro Prescimone ₁ , Edwin C Constable ₁ , Henk J Bolink ₂ , Enrique Ortí ₂ , Catherine E Housecroft ₁

Affiliation

Herein, [Cu(P^P)(N^N)][PF6 ] complexes (P^P=bis[2-(diphenylphosphino)phenyl]ether (POP) or 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (xantphos); N^N=CF3 -substituted 2,2'-bipyridines (6,6'-(CF3 )2 bpy, 6-CF3 bpy, 5,5'-(CF3 )2 bpy, 4,4'-(CF3 )2 bpy, 6,6'-Me2 -4,4'-(CF3 )2 bpy)) are reported. The effects of CF3 substitution on their structure as well as their electrochemical and photophysical properties are also presented. The HOMO-LUMO gap was tuned by the N^N ligand; the largest redshift in the metal-to-ligand charge transfer (MLCT) band was for [Cu(P^P){5,5'-(CF3 )2 bpy}][PF6 ]. In solution, the compounds are weak yellow to red emitters. The emission properties depend on the substitution pattern, but this cannot be explained by simple electronic arguments. Among powders, [Cu(xantphos){4,4'-(CF3 )2 bpy}][PF6 ] has the highest photoluminescence quantum yield (PLQY; 50.3 %) with an emission lifetime of 12 μs. Compared to 298 K solution behavior, excited-state lifetimes became longer in frozen Me-THF (77 K; THF=tetrahydrofuran), thus indicating thermally activated delayed fluorescence (TADF). Time-dependent (TD)-DFT calculations show that the energy gap between the lowest-energy singlet and triplet excited states (0.12-0.20 eV) permits TADF. Light-emitting electrochemical cells (LECs) with [Cu(POP)+(6-CF3 bpy)][PF6 ], [Cu(xantphos)(6-CF3 bpy)][PF6 ], or [Cu(xantphos){6,6'-Me2 -4,4'-(CF3 )2 bpy}][PF6 ] emit yellow electroluminescence. The LEC with [Cu(xantphos){6,6'-Me2 -4,4'-(CF3 )2 bpy}][PF6 ] had the fastest turn-on time (8 min), and the LEC with the longest lifetime (t1/2 =31 h) contained [Cu(xantphos)(6-CF3 bpy)][PF6 ]; these LECs reached maximum luminances of 131 and 109 cd m-2 , respectively.

中文翻译：

CF3取代[Cu（P ^ P）（bpy）] [PF6]配合物：对光物理性质和发光电化学电池性能的影响。

在此，[Cu（P ^ P）（N ^ N）] [PF6]络合物（P ^ P =双[2-（二苯基膦基）苯基]醚（POP）或4,5-双（二苯基膦基）-9,9 -二甲基x吨（黄药）; N ^ N = CF3-取代的2,2'-联吡啶（6,6'-（CF3）2 bpy，6-CF3 bpy，5,5'-（CF3）2 bpy，4,4报告了'-（CF3）2 bpy，6,6'-Me2 -4,4'-（CF3）2 bpy））。还介绍了CF3取代对其结构以及其电化学和光物理性质的影响。HOMO-LUMO缺口由N ^ N配体调节；金属-配体电荷转移（MLCT）带中最大的红移是[Cu（P ^ P）{5,5'-（CF3）2 bpy}] [PF6]。在溶液中，化合物为弱黄色至红色发射体。发射特性取决于取代模式，但这不能用简单的电子论据来解释。在粉末中，[Cu（xantphos）{4,4' -（CF3）2 bpy}] [PF6]的光致发光量子产率最高（PLQY； 50.3％），发射寿命为12 s。与298 K溶液行为相比，在冷冻的Me-THF（77 K； THF =四氢呋喃）中，激发态寿命更长，因此表明存在热激活的延迟荧光（TADF）。时间相关（TD）-DFT计算表明，最低能量单重态和三重态激发态（0.12-0.20 eV）之间的能隙允许TADF。具有[Cu（POP）+（6-CF3 bpy）] [PF6]，[Cu（xantphos）（6-CF3 bpy）] [PF6]或[Cu（xantphos）{6 ，6'-Me2 -4,4'-（CF3）2 bpy}] [PF6]发出黄色电致发光。具有[Cu（xantphos）{6,6'-Me2 -4,4'-（CF3）2 bpy}] [PF6]的LEC具有最快的开启时间（8分钟），寿命最长（t1 / 2 = 31 h）的LEC含有[Cu（xantphos）（6-CF3 bpy）] [PF6]；这些LEC分别达到131和109 cd m-2的最大亮度。

更新日期：2018-02-05

点击分享查看原文

点击收藏

公开下载

阅读更多本刊最新论文本刊介绍/投稿指南11