Abstract: Achieving high-performance carbon dots-based LED (CDLED) has long been a dream of the scientific community on account of its intrinsic merits of non-toxicity, cost-effectivity, environment-friendliness and high stability. However, the bottleneck problems of low external quantum efficiency (EQE) and poor color purity limit the application of deep-blue CDLED. This work reports a series of rhombus CDs with a graphitized core and alkyl passivation shell. The optimal m-CD exhibits dramatically high photoluminescence quantum yield (PLQY) of 97.2% in the solution and 82% in solid, exceeding all the previously reported CD materials for LED devices. Deep-blue CDLED using m-CD as an emitter demonstrates a bright, efficient and high-color-purity emission, with a maximum luminance of 740.6 cd m⁻², maximum EQE of 4.51% and CIE coordinates of (0.15, 0.07) closely approaching the high-definition television standard color Rec. BT.709 (0.15, 0.06) specification. The EQE_max of m-CDLED device notably exceeds all previously reported blue LEDs using carbon quantum dots as emitter. This work will set the stage for developing the next generation of high-performance deep-blue CDLED.

P. Huang; J.-R. Yu; M.-Z. Li; M.-H. Zhou; F. W. Dagnaw; J.-X. Jian*; Q.-X. Tong*, Engineering rhombus carbon quantum dots for high-performance deep-blue LEDs with external quantum efficiency exceeding 4.5%. ACS Sustain. Chem. Eng. 2023, 10.1021/acssuschemeng.3c01817.

链接：https://pubs.acs.org/doi/10.1021/acssuschemeng.3c01817