title: Common origin of green luminescence in carbon nanodots and graphene quantum dots.
abstract: Carbon nanodots (C-dots) synthesized by electrochemical ablation and small molecule carbonization, as well as graphene quantum dots (GQDs) fabricated by solvothermally cutting graphene oxide, are three kinds of typical green fluorescence carbon nanomaterials. Insight into the photoluminescence origin in these fluorescent carbon nanomaterials is one of the important matters of current debates. Here, a common origin of green luminescence in these C-dots and GQDs is unraveled by ultrafast spectroscopy. According to the change of surface functional groups during surface chemical reduction experiments, which are also accompanied by obvious emission-type transform, these common green luminescence emission centers that emerge in these C-dots and GQDs synthesized by bottom-up and top-down methods are unambiguously assigned to special edge states consisting of several carbon atoms on the edge of carbon backbone and functional groups with C═O (carbonyl and carboxyl groups). Our findings further suggest that the competition among various emission centers (bright edge states) and traps dominates the optical properties of these fluorescent carbon nanomaterials.
authors: State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, ‡State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, and §College of Physics, Jilin University , 2699 Qianjin Street, Changchun 130012, China.
authors: Lei
authors: L
authors: Wang
authors: Shou-Jun
authors: SJ
authors: Zhu
authors: Hai-Yu
authors: HY
authors: Wang
authors: Song-Nan
authors: SN
authors: Qu
authors: Yong-Lai
authors: YL
authors: Zhang
authors: Jun-Hu
authors: JH
authors: Zhang
authors: Qi-Dai
authors: QD
authors: Chen
authors: Huai-Liang
authors: HL
authors: Xu
authors: Wei
authors: W
authors: Han
authors: Bai
authors: B
authors: Yang
authors: Hong-Bo
authors: HB
authors: Sun