Red, phosphorescent OLEDs: New, bipolar materials, photophysical characterization, charge transport and OLED optimization

由宽带隙半导体低聚物和聚合物与磷光、红光发射金属配体配合物组合组成的发光二极管在显示技术以及大面积彩色照明应用中提供了有利的前景。通过低成本、湿化学可加工性与高效和纯的红色发射颜色的组合产生这些优点，这对于例如用于电视和个人计算机屏幕的全色大面积平板显示器或作为红色照明面板的开发是重要的。这个联合项目致力于开发宽带隙半导体低聚物和聚合物的智能组合，这些低聚物和聚合物与磷光红光发射铱（III）和锇（II）金属配体配合物混合。这些络合物的配体设计使得电子和空穴传输部分连接到螯合单元，从而与这些将直接连接到金属核的高度共轭的配体系统相互作用。这种设计允许在磷光物质处的有效电荷复合，预期导致三重态系统的更有效、颜色纯的红光发射。这些材料组合物中的能量传递、电荷产生和输运的研究和优化将被进行，对改进的和高效的饱和红光发光二极管的设计具有有益的影响。

Light-emitting diodes consisting of wide bandgap semiconducting oligomers and polymers combined with phosphorescent, red light-emitting metal-ligand complexes offer favorable perspectives in display technology as well as in large area colored lighting applications. The advantages result through a combination of low cost, wet-chemical processability with a highly efficient and pure, red emission color, which is of importance to the development of e.g. full color large area flat panel displays for television - and personal computer screens or as red colored lighting panels. This joint project addresses the development of smart combinations of wide bandgap semiconducting oligomers and polymers that are blended with phosphorescent red light-emitting iridium(lll) and osmium(ll) metal-ligand complexes. The ligand design of these complexes is such that electron and hole transporting moieties are connected to the chelating units and thus are interacting with these highly conjugated ligand systems that will be directly attached to the metal core. This design is allowing efficient charge recombination at the phosphorescent species expected to result in more efficient, color pure, red light emission of the triplet systems. Investigation and optimization of energy transfer, charge generation and transport in these material compositions will be carried out, being of beneficial impact towards the design of improved and highly efficient, saturated red light-emitting diodes.