Acta Chimica Sinica ›› 2021, Vol. 79 ›› Issue (10): 1281-1285.DOI: 10.6023/A21070333 Previous Articles     Next Articles



余梦b, 张子俊a, 朱国委a, 谷振华a, 段玉霖a, 余良翀a, 高冠斌a,*(), 孙涛垒a,b,*()   

  1. a 武汉理工大学 材料复合新技术国家重点实验室 武汉 430070
    b 武汉理工大学 化学化工与生命科学学院 武汉 430070
  • 投稿日期:2021-07-16 发布日期:2021-08-13
  • 通讯作者: 高冠斌, 孙涛垒
  • 作者简介:
    † 共同第一作者
  • 基金资助:
    国家自然科学基金(21975191); 国家自然科学基金(21805218); 国家自然科学基金(51873168); 国家级大学生创新创业训练计划(202110497008)

Synthesis of Ag2S Based Quantum Dots with Near-infrared-II Fluorescence Emission in Water

Meng Yub, Zijun Zhanga, Guowei Zhua, Zhenhua Gua, Yulin Duana, Liangchong Yua, Guanbin Gaoa(), Taolei Suna,b()   

  1. a State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070
    b School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070
  • Received:2021-07-16 Published:2021-08-13
  • Contact: Guanbin Gao, Taolei Sun
  • About author:
    † These authors contributed equally to this work
  • Supported by:
    National Natural Science Foundation of China(21975191); National Natural Science Foundation of China(21805218); National Natural Science Foundation of China(51873168); National innovation and Entrepreneurship Training Program for College Students(202110497008)

Growing numbers of quantum dots (QDs) have been applied in biological fluorescence imaging, especially those QDs with near-infrared-II fluorescence emission, avoiding the interference of autofluorescence of biological tissues, have broad application prospects in the field of fluorescence imaging. In particularly, Ag2S quantum dots (Ag2S QDs) have drew great attention of researchers in biological fluorescence imaging due to the near-infrared fluorescence emission, large Stokes shift, good light and chemical stability. However, the Ag2S QDs synthesized in organic phase usually experienced poor water solubility and biocompatibility, while the fluorescence of the Ag2S QDs synthesized in aqueous phase is difficult to reach the near-infrared-II region, which severely restricts the promotion of Ag2S QDs in biological fluorescence imaging. Therefore, it is of great significance to optimize and explore the water-phase synthesis method of Ag2S based quantum dots with near-infrared-II fluorescence emission. The goal of this work is to synthesize Ag2S QDs with near-infrared-II region fluorescence emission by aqueous phase method. First, captopril modified Ag2S QDs (Ag2S@Cap QDs) were prepared in water, and its fluorescence emission peak lied in the near-infrared-II region at 1005 nm. Then a series of Zn:Ag2S@Cap QDs were prepared in aqueous by introducing ZnS to the Ag2S core. The results showed that the fluorescence emission peaks of Zn:Ag2S@Cap QDs blue shifted in a core-doping ZnS-dose dependent manner. Next, a series of Ag2S@Cap-Zn QDs were prepared in aqueous by introducing Zn2+ to the ligand-shell of Ag2S QDs. The fluorescence emission peaks of these Ag2S@Cap-Zn QDs also blue shifted in a Zn2+-dose dependent manner. Finally, Ag2S@MUA QDs were prepared by replacing the shell ligand from Cap to 11-mercaptoundecanoic acid (MUA). The fluorescence emission peak of these Ag2S@MUA QDs red shifted to 1105 nm, locating in the near-infrared-II region, and the width of the fluorescence curve at half-maximum height became narrower, implying better application prospect in biological fluorescence imaging. This work not only successfully prepared a kind of Ag2S QDs with near-infrared-II fluorescence emission in aqueous phase, but also opened an avenue for the preparation and optimization of semiconductor QDs with near-infrared fluorescence.

Key words: near-infrared-Ⅱ fluorescence, Ag2S QDs, aqueous synthesis, core-doping, cationic-modification, optimizing surface ligand