Open AccessOne-Step Synthesis of Acidophilic Highly-Photoluminescent Carbon Dots Modified by Ionic Liquid from Polyethylene Glycol
Author(s) -
Yujuan Chen,
Qian Yang,
Panpan Xu,
Li Sun,
Dong Sun,
Kelei Zhuo
Publication year - 2017
Publication title -
acs omega
Language(s) - English
Resource type - Journals
ISSN - 2470-1343
DOI - 10.1021/acsomega.7b01014
Subject(s) - ionic liquid , photoluminescence , polyethylene glycol , hydrochloric acid , bromide , materials science , chemistry , inorganic chemistry , organic chemistry , catalysis , optoelectronics
Acidophilic highly-photoluminescent ionic liquid (IL)-modified carbon dots (CDs) were fabricated directly from polyethylene glycol-2000 (PEG 2000N ) by a simple one-step hydrothermal method in a system containing an IL (1-butyl-3-methylimidazolium bromide [C 4 mim]Br) and hydrochloric acid (HCl). In this process, PEG 2000N works as the carbon source, [C 4 mim]Br as the modifier, and HCl as the accelerator. CDs with low photoluminescence (PL) intensity and quantum yields (QYs) were generated in the system without H + , but CDs with high PL intensity and QYs could be prepared after H + was introduced. Moreover, with the increase of H + concentration, the QYs of the prepared CDs increase subsequently, and the highest QY reaches up to 43%. The formation mechanism was explored, and the results showed that H + changes the surface groups of the CDs generated without H + into those that exist on the CDs generated with H + , which further improves the PL performance of the CDs. Different from most CDs reported in the literature, the as-prepared CDs can still exhibit high PL intensity even under strong acidic condition.