J. Mater. Sci. Technol. ›› 2023, Vol. 134: 189-196.DOI: 10.1016/j.jmst.2022.06.035

• Research Article • Previous Articles     Next Articles

Aqueous synthesis of 79% efficient AgInGaS/ZnS quantum dots for extremely high color rendering white light-emitting diodes

Zhe Hua,1, Hanxu Lua,1, Wenjie Zhoua, Jinxin Weia, Hanqing Daib, Hong Liua, Zhiyong Xiongb, Fengxian Xiea,c, Wanlu Zhanga,*(), Ruiqian Guoa,b,c,d,*()   

  1. aInstitute for Electric Light Sources, School of Information Science and Technology, Fudan University, Shanghai 200433, China
    bInstitute of Future Lighting, Academy for Engineering and Technology, Fudan University, Shanghai 200433, China
    cZhongshan - Fudan Joint Innovation Center, Zhongshan 528437, China
    dYiwu Research Institute of Fudan University, Yiwu 322000, China
  • Received:2022-05-20 Revised:2022-06-11 Accepted:2022-06-15 Published:2023-01-20 Online:2023-01-10
  • Contact: Wanlu Zhang,Ruiqian Guo
  • About author:rqguo@fudan.edu.cn (R. Guo).
    * Institute for Electric Light Sources, School of Information Science and Technology, Fudan University, Shanghai 200433, China. E-mail addresses: fdwlzhang@fudan.edu.cn (W. Zhang),
    First author contact:1These authors contributed equally to this work.

Abstract:

Over the past few decades, I-III-VI quantum dots (QDs) have attracted considerable attention due to their large Stokes shifts, good eco-friendliness, and wide tunable emissions. In this work, a facile microwave-assisted aqueous route using glutathione (GSH) and citric acid (CA) as dual stabilizers is introduced to synthesize AgInGaS/ZnS (AIGS/ZnS) core/shell QDs. An exceptional photoluminescence quantum yield (PL QY) as high as 79% is successfully achieved, boosting the best performance of water-dispersible AIGS QDs. By varying the Ag/Ga ratio, the PL peak wavelength can be tuned from 547 to 616 nm, and luminescent hydrogel films with different colors are obtained by embedding AIGS/ZnS QDs in polyacrylamide/poly-vinyl alcohol (PAAm/PVA) hydrogels. The white light-emitting diode (WLED) with a high color rendering index (CRI) of 92.1 (R9=92.0) and a correlated color temperature (CCT) of 3022 K is fabricated using QDs-PAAm/PVA hydrogel films in combination with a blue InGaN LED chip, indicating that the as-prepared QDs are competitive color-conversion materials for WLEDs.

Key words: AgInGaS/ZnS, Aqueous synthesis, Quantum dots, White LEDs