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  • Ultra-stable blue-emitting lead-free double perovskite Cs 2 SnCl 6 nanocrystals enabled by an aqueous synthesis on a microfluidic platform
Title: Ultra-stable blue-emitting lead-free double perovskite Cs 2 SnCl 6 nanocrystals enabled by an aqueous synthesis on a microfluidic platform
Blue emitting Sn-based lead-free halide perovskite nanocrystals (NCs) are considered to be a promising material in lighting and displays. However, industrialised fabrication of blue-emitting NCs still remains a significant challenge due to the use of toxic solvents and optical instability, not mentioning in large-scale synthesis. In this work, a green-route synthesis of blue-emitting lead-free halide perovskite Cs 2 SnCl 6 powders is developed, in which deionized water with a small amount of inorganic acid is used as the solvent and the synthesis of the Cs 2 SnCl 6 powders is achieved on a microfluidic platform. Using the Cs 2 SnCl 6 powders, we prepare Cs 2 SnCl 6 NCs via an ultrasonication process. Changing the volume ratio of the ligands (oleic acid to oleylamine) can alter the photoluminescence (PL) characteristics of the prepared NCs, including the PL-peak wavelength, PL-peak intensity and quantum yield. The highest photoluminescence quantum yield (PLQY) of 13.4% is achieved by the Cs 2 SnCl 6 NCs prepared with the volume ratio of oleic acid to oleylamine of 40 μL to 10 μL. A long-term PL stability test demonstrates that the as-synthesized Cs 2 SnCl 6 NCs can retain a stable PLQY over a period of 60 days. This work opens up a new path for a large-scale green-route synthesis of blue-emitting Sn-based lead-free NCs, such as Cs 2 SnX 6 (Cl, Br and I), towards their applications in optoelectronics.  more » « less
Award ID(s):
2018411 1854554
PAR ID:
10430085
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Nanoscale
Volume:
14
Issue:
47
ISSN:
2040-3364
Page Range / eLocation ID:
17641 to 17653
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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