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.

在柔性衬底上实现廉价的、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）配合物构成一类三重态发光体，其表现出正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，从而导致有机发光二极管（OLED）的可调颜色。我们最近开发了一种策略，以获得平坦的Pt（II）配合物，可以升华和沉积在金属基板上形成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），我们在亚分子水平上研究了Au（111）界面的结构和电子性质。在限定位置的化学取代使得能够实现深蓝色磷光体。我们现在将使用四配位基发光体，提供光电器件所需的最终稳定性，而与加工方法无关。磷光聚集体将通过找到亚分子和分子间电子固定螺钉（即合适的配体和取代基）而从蓝色调谐到红色。分子间的相互作用将通过改变金属中心的电子密度和取代基的体积来控制。化学合成和积分光谱研究将由一系列基于DFT的静态和动态方法指导，用于预测稳定性和激发态性质。聚集体的形成和稳定性以及它们的发光特性将作为溶液中的温度的函数和对于不同的衬底通过从头算模拟进行研究。最好的候选者将用于实现溶液处理和气相沉积的OLED。当蓝绿色发光体堆叠成红色团簇时，可以通过调节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发生，因此可以设想简化的器件，只要在电极表面上形成多色磷光聚集体层并直接电激发。因此，单层，双层和多层堆叠复合物将研究其电子性质，导电性和（电）发光在导电界面。采用STM和STS，通过突出的轨道瓣的平面发射器与下面的金属表面的局部耦合将与电荷注入现象向简化的OLED阵列相关。STM诱导的电致发光和photomapping与空间，光谱和时间分辨率将使一个详细的了解个别复合物的聚集体和多层。

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