Bonding, charge transfer and aggregation of luminescent Platinum complexes at metallic interfaces

金属界面上发光铂配合物的键合、电荷转移和聚集

• 批准号: 333051277
• 负责人: Professor Dr. Nikos L. Doltsinis
• 金额: --
• 依托单位: Institut für Festkörpertheorie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/333051277?language=en
• 关键词: Bonding; charge; transfer; aggregation; luminescent

The realization of cheap, printable optoelectronic devices on flexible substrates requires a fundamental understanding of molecular aggregation and interactions with interfaces. Pt(II) complexes constitute a class of triplet emitters exhibiting a square planar coordination geometry that favors the coupling of d-orbitals in phosphorescent aggregates, resulting in tunable colors for organic light-emitting diodes (OLEDs). We have recently developed a strategy to obtain flat Pt(II) complexes that can be sublimed and deposited on metal substrates forming 2D monolayers. With the aid of scanning tunneling microscopy (STM) and spectroscopy (STS) as well as density functional theory (DFT), we explored structural and electronic properties at the Au(111) interface with submolecular resolution. Chemical substitution at defined positions enabled the realization of deep-blue phosphors. We will now use tetradentate luminophores providing the ultimate stability required for optoelectronic devices, irrespective of the processing method. The phosphorescent aggregates will be tuned from blue to red by finding the sub- and intermolecular electronic set-screws, i.e. suitable ligands and substituents. Intermolecular interactions will be controlled by varying the electron density at the metal center and the bulk of the substituents. Chemical synthesis and integral spectroscopic studies will be guided by a range of static and dynamic DFT-based methods for the prediction of stabilities and excited state properties. The formation and stability of aggregates as well as their luminescent properties will be investigated as a function of temperature in solution and for different substrates by ab inito simulation. The best candidates will be used for the realization of solution-processed and vapor-deposited OLEDs. When blue-green emitters stack into red clusters, white OLEDs can be realized by adjusting the degree of aggregation. As charge injection can occur via direct coupling of d-orbitals from the first layer with the electrodes, simplified devices can be envisaged, provided that layers of polychromatic phosphorescent aggregates are formed and directly electrically excited on the surface of electrodes. Thus, mono-, bi- and multilayers of stacked complexes will be investigated regarding their electronic properties, conductivity and (electro-)luminescence at conductive interfaces. Employing STM and STS, local coupling of the planar emitters with the underlying metallic surface via protruding orbital lobes will be correlated with charge injection phenomena towards simplified OLED arrays. STM-induced electroluminescence and photomapping with spatial, spectral and temporal resolution will enable a detailed understanding of the individual complexes in aggregates and in multilayers.

在柔性基板上实现廉价、可印刷的光电器件需要对分子聚集和与界面的相互作用有基本的了解。 Pt(II) 配合物构成一类三线态发射体，具有方形平面配位几何形状，有利于磷光聚集体中 d 轨道的耦合，从而为有机发光二极管 (OLED) 提供可调颜色。我们最近开发了一种获得扁平 Pt(II) 配合物的策略，该配合物可以升华并沉积在金属基底上形成 2D 单层。借助扫描隧道显微镜（STM）和光谱学（STS）以及密度泛函理论（DFT），我们以亚分子分辨率探索了Au（111）界面的结构和电子特性。在特定位置进行化学取代可以实现深蓝色荧光粉。我们现在将使用四齿发光体，无论采用何种加工方法，都能提供光电器件所需的最终稳定性。通过找到子分子和分子间电子固定螺丝，即合适的配体和取代基，磷光聚集体将从蓝色调整为红色。分子间相互作用将通过改变金属中心和取代基体积的电子密度来控制。化学合成和积分光谱研究将由一系列基于静态和动态 DFT 的方法指导，用于预测稳定性和激发态特性。通过从头模拟，将研究聚集体的形成和稳定性以及它们的发光特性作为溶液中温度的函数以及不同基底的变化。最好的候选者将用于实现溶液处理和气相沉积 OLED。当蓝绿色发射体堆叠成红色簇时，可以通过调整聚集程度来实现白色OLED。 由于电荷注入可以通过来自第一层的d轨道与电极的直接耦合来发生，因此可以设想简化的装置，只要形成多色磷光聚集体层并在电极表面上直接电激发。因此，将研究单层、双层和多层堆叠复合物的电子特性、电导率和导电界面处的（电）发光。采用 STM 和 STS，平面发射器通过突出的轨道瓣与底层金属表面的局部耦合将与简化 OLED 阵列的电荷注入现象相关。 STM 诱导的电致发光和具有空间、光谱和时间分辨率的光映射将使人们能够详细了解聚集体和多层中的单个复合物。

项目成果

Conformation-dependent phosphorescence emission of individual mononuclear ruthenium-(ii)-bis-terpyridine complexes.

单个单核钌-(ii)-双三联吡啶配合物的构象依赖性磷光发射

• DOI: 10.1039/c8cp04580a
• 发表时间: 2018
• 期刊: Physical chemistry chemical physics : PCCP
• 作者: T. Koch;C. Höppener;N. L. Doltsinis
• 通讯作者: N. L. Doltsinis

Quantitative assessment of intermolecular interactions by atomic force microscopy imaging using copper oxide tips

• DOI: 10.1038/s41565-018-0104-4
• 发表时间: 2018-05-01
• 期刊: NATURE NANOTECHNOLOGY
• 影响因子: 38.3
• 作者: Moenig, Harry;Amirjalayer, Saeed;Fuchs, Harald
• 通讯作者: Fuchs, Harald

Fluorination-controlled Aggregation and Intermolecular Interactions in Pt(II) Complexes with Tetradentate Luminophores

• DOI: 10.1002/ijch.201800050
• 发表时间: 2018-07
• 期刊: Israel Journal of Chemistry
• 影响因子: 3.2
• 作者: S. Wilde;Darío González-Abradelo;C. Daniliuc;M. Böckmann;N. Doltsinis;C. Strassert

Toward Tunable Electroluminescent Devices by Correlating Function and Submolecular Structure in 3D Crystals, 2D-Confined Monolayers, and Dimers.

• DOI: 10.1021/acsami.8b03528
• 发表时间: 2018-06
• 期刊: ACS applied materials & interfaces
• 影响因子: 9.5
• 作者: S. Wilde;Dongxin Ma;Tobias Koch;A. Bakker;Darío González-Abradelo;L. Stegemann;C. Daniliuc;H. Fuchs;Hongying Gao;N. Doltsinis;Lian Duan;C. Strassert

On‐Surface Reactive Planarization of Pt(II) Complexes

• DOI: 10.1002/anie.201906247
• 发表时间: 2019-07
• 期刊: Angewandte Chemie (International Ed. in English)
• 作者: Jindong Ren;Marvin Cnudde;Dana Brünink;Stefan Buss;C. Daniliuc;Lacheng Liu;H. Fuchs;C. Strassert;Hongying Gao;N. Doltsinis