摘要
本研究合成了一支新型氮杂环卡宾铂配合物磷光材料，对其进行了核磁、质谱及光物理性质表征；并将其作为OLED发光材料，采用真空蒸镀法制备OLED器件，探究其电致发光性能。研究表明，该铂配合物在薄膜中的发光峰波长447nm，半峰宽19nm，是优异的蓝光发光。基于此配合物的OLED器件最大发射波长为450nm，CIE为（0.14，0.16）。该器件从5mA/cm2到20mA/cm2电流密度变化下，电流滚降小于5%，并且该掺杂材料的器件具有较高的效率，电流效率为14.2cd/A，功率效率为4.03lm/W，外量子效率为9.35%，说明此器件具有高效的发光性能，推动全色域OLED核心磷光发光材料的开发及应用。
关键词： OLED；磷光材料；铂配合物；氮杂环卡宾
Abstract
This study synthesized a novel phosphorescent material based on a Pt-complex with an N-heterocyclic carbene ligand. The complex was characterized using NMR, MS and photophysical property analysis. It was then employed as an emissive material in OLED devices fabricated via vacuum deposition to investigate its electroluminescent performance. The research indicates that this platinum complex exhibits excellent blue emission with a luminescence peak at 447 nm and a full width at half maximum (FWHM) of 19 nm in films. The OLED device based on this complex achieved a maximum emission wavelength of 450 nm with CIE coordinates of (0.14, 0.16). The device demonstrated minimal efficiency roll-off, with a decrease of less than 5% as the current density increased from 5 mA/cm² to 20 mA/cm². Furthermore, the doped device exhibited high efficiency, with a current efficiency of 14.2 cd/A, a power efficiency of 4.03 lm/W, and an external quantum efficiency (EQE) of 9.35%. These results indicate that the device possesses highly efficient luminescent properties, contributing to the development and application of core phosphorescent materials for full-color OLED displays.
Key words： OLED; Phosphorescent material; Pt-complex; N-Heterocyclic carbene
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