@article{Liu2022, 
author = {Yongfeng Liu and Shi Tang and Xiuyu Wu and Nicolas Boulanger and Eduardo Gracia-Espino and Thomas Wågberg and Ludvig Edman and Jia Wang},
title = {Carbon nanodots: A metal-free, easy-to-synthesize, and benign emitter for light-emitting electrochemical cells},
year = {2022},
journal = {Nano Research},
volume = {15},
number = {6},
pages = {5610-5618},
keywords = {carbon nanodot, light-emitting electrochemical cell, phloroglucinol, sustainable synthesis, solution-based fabrication},
url = {https://www.sciopen.com/article/10.1007/s12274-022-4126-8},
doi = {10.1007/s12274-022-4126-8},
abstract = {Light-emitting electrochemical cells (LECs) can be fabricated with cost-efficient printing and coating methods, but a current drawback is that the LEC emitter is commonly either a rare-metal complex or an expensive-to-synthesize conjugated polymer. Here, we address this issue through the pioneering employment of metal-free and facile-to-synthesize carbon nanodots (CNDs) as the emitter in functional LEC devices. Circular-shaped (average diameter = 4.4 nm) and hydrophilic CNDs, which exhibit narrow cyan photoluminescence (peak = 485 nm, full width at half maximum = 30 nm) with a high quantum yield of 77% in dilute ethanol solution, were synthesized with a catalyst-free, one-step solvothermal process using low-cost and benign phloroglucinol as the sole starting material. The propensity of the planar CNDs to form emission-quenching aggregates in the solid state was inhibited by the inclusion of a compatible 2,7-bis(diphenylphosphoryl)-9,9’-spirobifluorene host compound, and we demonstrate that such pristine host-guest CND-LECs turn on to a peak luminance of 118 cd·m−2 within 5 s during constant current-density driving at 77 mA·cm−2.}
}