Ultra-broadband triple-peak white light-emitting carbonized polymer dots materials based on Förster resonance energy transfer

Abstract

Carbonized polymer dots (CPDs) with white-light-emitting property have greatly promising application in next generation of lighting and display technologies. However, most of the reported CPD materials exhibit single peak emission and narrow emission band, resulting in difficulty to obtain white-light emission. In this work, the ultra-broadband triple-peak emission (red, green, and blue) CD-based materials with high-efficiency white light-emitting property are realized for the first time by the Förster resonance energy transfer (FRET). Blue and green emissions are derived from the fluorescence and phosphorescence of donor CPDs, while the red light is derived from receptor by FRET. Remarkably, the fabricated CPD materials show bright pure white-light emission with high overall quantum yield (QY) of 36% and the full width at half maximum of 235 nm. Besides, afterglow colors of CPD-based materials can be tuned from green to red by adjusting the ratio of donor and acceptor. Based on the high-efficiency and wide-spectrum pure white light emission characteristics of CPD-based composites, white light emitting diodes were fabricated and they exhibit bright warm white light with CIE and CCT of (0.35, 0.31) and 4041 K.