%0 Journal Article
%T Electroluminescent Warm White Light©\Emitting Diodes Based on Passivation Enabled Bright Red Bandgap Emission Carbon Quantum Dots
%A Fanglong Yuan
%A Haoran Jia
%A Louzhen Fan
%A Ting Yuan
%A Xiaohong Li
%A Yunchao Li
%A Zhan'ao Tan
%A Zhibin Wang
%J Archive of "Advanced Science".
%D 2019
%R 10.1002/advs.201900397
%X The development of efficient red bandgap emission carbon quantum dots (CQDs) for realizing high©\performance electroluminescent warm white light©\emitting diodes (warm©\WLEDs) represents a grand challenge. Here, the synthesis of three red©\emissive electron©\donating group passivated CQDs (R©\EGP©\CQDs): R©\EGP©\CQDs©\NMe2, ©\NEt2, and ©\NPr2 is reported. The R©\EGP©\CQDs, well soluble in common organic solvents, display bright red bandgap emission at 637, 642, and 645 nm, respectively, reaching the highest photoluminescence quantum yield (QY) up to 86.0% in ethanol. Theoretical investigations reveal that the red bandgap emission originates from the rigid ¦Ð©\conjugated skeleton structure, and the ©\NMe2, ©\NEt2, and ©\NPr2 passivation plays a key role in inducing charge transfer excited state in the ¦Ð©\conjugated structure to afford the high QY. Solution©\processed electroluminescent warm©\WLEDs based on the R©\EGP©\CQDs©\NMe2, ©\NEt2, and ©\NPr2 display voltage©\stable warm white spectra with a maximum luminance of 5248¨C5909 cd m£¿2 and a current efficiency of 3.65¨C3.85 cd A£¿1. The warm©\WLEDs also show good long©\term operational stability (L/L 0 > 80% after 50 h operation, L 0: 1000 cd m£¿2). The electron©\donating group passivation strategy opens a new avenue to realizing efficient red bandgap emission CQDs and developing high©\performance electroluminescent warm©\WLEDs
%K carbon quantum dots
%K electroluminescence
%K high quantum yield
%K red fluorescence
%K warm white light©\emitting diodes
%U https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6662328/