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Excitation wavelength independent visible color emission of carbon dots.

ABSTRACT: Carbon dots (CDs) usually emit a strong blue light and excitation wavelength dependent long wavelength lights. This significantly limits their applications because one has to use a series of different excitation light sources to get different colors and the long wavelength emissions are usually very weak. We found that one type of CDs synthesized from p-phenylenediamine could emit various long wavelength lights (green to red) independent of the excitation wavelength when dispersed in different solvents. The photoluminescence quantum yields of the same CDs were 10-35% in different solvents for different color emissions. Based on this solvent-color effect, we further mixed the same CDs with different polymers to form solid CD films for various color emissions, and these film emissions were also excitation wavelength independent. Multicolor LEDs were demonstrated with the same CDs in solution and solid film states for color displays.

SUBMITTER: Wang H

PROVIDER: S-EPMC6265045 | biostudies-other | 2017 Feb

REPOSITORIES: biostudies-other

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Excitation wavelength independent visible color emission of carbon dots.

Wang Hua H Sun Chun C Chen Xingru X Zhang Yu Y Colvin Vicki L VL Rice Quinton Q Seo Jaetae J Feng Shengyu S Wang Shengnian S Yu William W WW

Nanoscale 20170201 5

Carbon dots (CDs) usually emit a strong blue light and excitation wavelength dependent long wavelength lights. This significantly limits their applications because one has to use a series of different excitation light sources to get different colors and the long wavelength emissions are usually very weak. We found that one type of CDs synthesized from p-phenylenediamine could emit various long wavelength lights (green to red) independent of the excitation wavelength when dispersed in different s ...[more]

PMID: 28094404

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