Chemical Engineering Journal, Vol.320, 570-575, 2017
Solvothermal conversion of coal into nitrogen-doped carbon dots with singlet oxygen generation and high quantum yield
Fluorescent nitrogen-doped carbon dots (N-CDs) are synthesized by a facile one-pot solvothermal approach from Taixi anthratite in the presence of dimethyl formamide (DMF). Benefiting from superior dispersion of light components in DMF and easy exfoliation of smaller sp(2)-carbon structures from the anthracite, the as-prepared N-CDs show a strong photoluminescence (PL) with a high quantum yield (QY) of 47.0% and production yield of 25.6 wt%. Besides, the N-CDs also exhibit a singlet oxygen (102) generation behavior with a 102 generation QY of 19.0%. Moreover, the as-obtained N-CDs emit blue PL under the excitation wavelength of 365 nm, and can be easily dispersed in polymethyl methacrylate (PMMA), retaining the inherent advantages of the N-CDs and the PMMA matrix. The possible mechanism involved in the formation of N-CDs is proposed and discussed in terms of the macromolecular structure of the anthracite and the solvothermal approach adopted in the study. (C) 2017 Published by Elsevier B.V.
Keywords:Coal;Anthracite;Carbon;Nitrogen-doped carbon dots;Preparation;Solvothermal approach;Singlet oxygen generation;Quantum yield;Yield