Synthesis of Silver Sulfide Quantum Dots Via the Liquid\u2013Liquid Interface Reaction in a Rotating Packed Bed Reactor

Qing Liu,Jiexin Wang,Dan Wang,Yuan Pu,Zhijian Zhao

doi:10.1007/s12209-019-00228-5

Qing Liu, Jiexin Wang + Show 3 more

Open Access

https://doi.org/10.1007/s12209-019-00228-5

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Abstract

We developed the high-gravity coupled liquid–liquid interface reaction technique on the basis of the rotating packed bed (RPB) reactor for the continuous and ultrafast synthesis of silver sulfide (Ag2S) quantum dots (QDs) with near-infrared (NIR) luminescence. The formation of Ag2S QDs occurs at the interface of microdroplets, and the average size of Ag2S QDs was 4.5 nm with a narrow size distribution. Ag2S QDs can disperse well in various organic solvents and exhibit NIR luminescence with a peak wavelength at 1270 nm under 980-nm laser excitation. The mechanism of the process intensification was revealed by both the computational fluid dynamics simulation and fluorescence imaging, and the mechanism is attributed to the small and uniform droplet formation in the RPB reactor. This study provides a novel approach for the continuous and ultrafast synthesis of NIR Ag2S QDs for potential scale-up.

Highlights

In the last decades, quantum dots (QDs) have been used in biomedical imaging [1], television displays [2] and photovoltaic devices [3]
By combining the advantages of microchemical technology and high-gravity technology, we developed a high-gravity coupled liquid–liquid interface reaction technique on the basis of rotating packed bed (RPB) reactors for the continuous and ultrafast synthesis of NIR A g2S QDs
It is noted that the mixing of the two-phase solution in the RPB reactor differs from the mechanical mixing in stirred tank reactor (STR) [30]

Summary

Introduction

Quantum dots (QDs) have been used in biomedical imaging [1], television displays [2] and photovoltaic devices [3]. The effects of different high-gravity levels, liquid flow rate and circulation time on the product morphology and dispersion were investigated.

Results

Conclusion