Stable and efficient organic light-emitting diodes (OLEDs) operating at high brightness are desirable for future high-resolution displays and lighting products. Here, we report a tetradentate Pd(ii) complex called Pd3O8-P, which has attractive optoelectronics properties. At room temperature, aggregates of Pd3O8-P exhibited a close-to-unity photoluminescent quantum yield and a short transient lifetime of 0.62 μs. A host-free Pd3O8-P yellow-orange OLED emitted light with a peak at 588 nm, a half-bandwidth of 84 nm and CIE coordinates of (0.52, 0.47), and achieved a peak external quantum efficiency (EQE) of 34.8%. The device had reduced efficiency roll-off, retaining high EQEs of 33.5% at 1,000 cd m⁻² and 29.5% at 10,000 cd m⁻². The estimated operational half-lifetime was 9.59 million hours at 1,000 cd m⁻². The fact that the tetradentate metal complex has a triplet in the blue-emitting region may also assist the development of efficient and long-lived blue OLEDs in the future.

在未来的高分辨率显示器和照明产品中，需要在高亮度下工作的稳定高效的有机发光二极管（OLED）。在这里，我们报道了一种称为Pd3O8-P的四齿Pd（ii）络合物，它具有诱人的光电特性。在室温下，Pd3O8-P的聚集体表现出接近统一的光致发光量子产率和0.62μs的短瞬态寿命。无主体的Pd3O8-P橙橙色OLED发出的光的峰值为588 nm，半带宽为84 nm，CIE坐标为（0.52，0.47），并且达到了34.8％的峰值外部量子效率（EQE）。 。该器件降低了效率衰减，在1,000 cd m ^-2时保持了33.5％的高EQE，在10,000 cd m ^-2时保持了29.5％的高EQE。在1,000 cd m ^-2时，估计的工作半衰期为959万小时。四齿金属络合物在发射蓝色光的区域中具有三重态的事实也可能有助于将来开发高效且长寿命的蓝色OLED。