Multicolor Nitrogen-Doped Carbon Quantum Dots for Environment-Dependent Emission Tuning.

Content Provider	Europe PMC
Author	Sengottuvelu, Dineshkumar Shaik, Abdul Kalam Mishra, Satish Ahmad, Humayun Abbaszadeh, Mahsa Hammer, Nathan I. Kundu, Santanu
Copyright Year	2022
Abstract	Carbon quantum dots (CQDs) have potential applicationsin manyfields such as light-emitting devices, photocatalysis, and bioimagingdue to their unique photoluminescence (PL) properties and environmentalbenignness. Here, we report the synthesis of nitrogen-doped carbonquantum dots (NCQDs) from citric acid and m-phenylenediamineusing a one-pot hydrothermal approach. The environment-dependent emissionchanges of NCQDs were extensively investigated in various solvents,in the solid state, and in physically assembled PMMA–PnBA–PMMAcopolymer gels in 2-ethyl-hexanol. NCQDs display bright emissionsin various solvents as well as in the solid state. These NCQDs exhibitmulticolor PL emission across the visible region upon changing theenvironment (solutions and polymer matrices). NCQDs also exhibit excitation-dependentPL and solvatochromism, which have not been frequently investigatedin CQDs. Most CQDs are nonemissive in the aggregated or solid statedue to the aggregation-caused quenching (ACQ) effect, limiting theirsolid-state applications. However, NCQDs synthesized here displaya strong solid-state emission centered at 568 nm attributed to thepresence of surface functional groups that restrict the π–πinteraction between the NCQDs and assist in overcoming the ACQ effectin the solid state. NCQD-containing gels display significant fluorescenceenhancement in comparison to the NCQDs in 2-ethyl hexanol, likelybecause of the interaction between the polar PMMA blocks and NCQDs.The application of NCQDs-Gel as a solid/gel state fluorescent displayhas been presented. This research facilitates the development of large-scale,low-cost multicolor phosphor for the fabrication of optoelectronicdevices, sensing, and bioimaging applications.
Journal	ACS Omega
Volume Number	7
PubMed Central reference number	PMC9366982
Issue Number	31
PubMed reference number	35967036
e-ISSN	24701343
DOI	10.1021/acsomega.2c03912
Language	English
Publisher	American Chemical Society
Publisher Date	2022-08-01
Access Restriction	Open
Rights License	Permits non-commercial access and re-use, provided that author attribution and integrity are maintained; but does not permit creation of adaptations or other derivative works (https://creativecommons.org/licenses/by-nc-nd/4.0/). © 2022 The Authors. Published by American Chemical Society
Content Type	Text
Resource Type	Article
Subject	Chemistry Chemical Engineering