Scalable and atom economic preparation of red-near-infrared emitted N-doped graphene quantum dots with a high quantum yield

• Published in: Diamond and related materials 2021-06, Vol.116, p.108395, Article 108395
• Main Authors: Zhu, Wei, Feng, Xiaoqiang, Zhao, Menghan, Wei, Zhiheng, Liu, Zhiduo, Wang, Gang, Guo, Qinglei, Chen, Da
• Format: Article
• Language: English
• Subjects: Bio-imaging; Emission; Environmental-friendly preparation; Graphene; Graphene quantum dots; High quantum yield; Indigo; Near infrared radiation; Nitrogen; Quantum dots; Red-near-infrared emission
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/j.diamond.2021.108395

The development of an environmental-friendly and scalable preparation approach for graphene quantum dots (GQDs) with high quantum yield is a focus area for GQDs. Hence, we describe an atom economic green chemistry strategy for nitrogen-doped GQDs (N-GQDs). The yield of N-GQDs is 98.5%. Moreover, due to the simple reaction and processes, N-GQDs can be synthesized on a large scale (the throughput of N-GQDs is 10 g). Besides, the intrinsic bandgap PL of N-GQDs can be adjusted by size modulation. The emission wavelength of N-GQDs is modulated from 405 nm to 698 nm with a high quantum yield (0.89–0.62). Furthermore, with the general nucleophilic addition reaction of indigo, the PL response-ability of the obtained GQDs can be further tuned. Different precursors with heteroatoms (such as S and Se) can be used for the preparation of dual- heteroatoms co-doped GQDs (N, S-GQDs and N, Se-GQDs). We also confirmed the utilization of the red-near-infrared emitted N-GQDs (emission wavelength: 698 nm) with high quantum yield (0.62) in bio-imaging. [Display omitted] •An environment-friendly, scalable preparation approach for GQDs was developed.•The yield of GQDs is 98.5 wt%•The preparation approach is atom economic.•The emission wavelength of N-GQDs is modulated with a high quantum yield.