• 文献标题:   Facile synthesis of graphene quantum dots with red emission and high quantum yield
  • 文献类型:   Article
  • 作  者:   JIN XJ, TAN L, ZHAO ZQ, LI MC, ZHOU QY, ZHANG JJ, LV TB, DENG Q, WANG J, ZENG ZL, DENG SG, DAI GP
  • 作者关键词:  
  • 出版物名称:   NEW JOURNAL OF CHEMISTRY
  • ISSN:   1144-0546 EI 1369-9261
  • 通讯作者地址:  
  • 被引频次:   0
  • DOI:   10.1039/d2nj04491a EA JAN 2023
  • 出版年:   2023

▎ 摘  要

Graphene quantum dots (GQDs) are promising for bioimaging applications due to their unique optical properties and good biocompatibility. However, the facile synthesis of GQDs with long-wavelength emission and high quantum yield (QY) under long-wavelength excitation is still a challenge. Herein, dual-emissive GQDs were synthesized via a facile one-pot solvothermal method using 2,7-dihydroxynaphthalene (2,7-DHN) and piperazine anhydrous (PA) as the raw materials. The obtained GQDs exhibited a green-emission band (core state emission) and a red-emission band (surface state emission), which originated from the inner pi-conjugated structure and various surface functional groups, respectively. The pi-conjugated structure mainly comes from the aromatic rings in 2,7-DHN, and the N-H of PA acts as the main nitrogen source, which is beneficial for the QY. The obtained GQDs showed obvious concentration-dependent optical properties. Importantly, they are able to generate red emission with a high absolute QY of 54.9% in ethanol and 24.9% in water, among the best values of reported GQDs. In addition, the prepared GQDs have good water-solubility, low cytotoxicity, and superior stability against photobleaching. Based on the above advantages, the as-prepared GQDs were successfully applied for labeling HeLa cells in vitro. Therefore, our prepared GQDs demonstrated that they can be an efficient biomarker for fluorescent bioimaging.