Enhanced Air Stability of Perovskite Quantum Dots by Manganese Passivation

Ryota Sato,Kazuki Umemoto,Satoshi Asakura,Akito Masuhara

doi:10.3390/technologies10010010

Abstract

Organic-inorganic perovskite quantum dots (PeQDs) have attracted attention due to their excellent optical properties, e.g., high photoluminescence quantum yields (PLQYs; >70%), a narrow full width at half maximum (FWHM; 25 nm or less), and color tunability adjusted by the halide components in an entire tunability (from 450 nm to 730 nm). On the other hand, PeQD stability against air, humidity, and thermal conditions has still not been enough, which disturbs their application. To overcome these issues, with just a focus on the air stability, Mn2+ ion passivated perovskite quantum dots (Mn/MAPbBr3 QDs) were prepared. Mn2+ could be expected to contract the passivating layer against the air condition because the Mn2+ ion was changed to the oxidized Mn on PeQDs under the air conditions. In this research, Mn/MAPbBr3 QDs were successfully prepared by ligand-assisted reprecipitation (LARP) methods. Surprisingly, Mn/MAPbBr3 QD films showed more than double PLQY stability over 4 months compared with pure MAPbBr3 ones against the air, which suggested that oxidized Mn worked as a passivating layer. Improving the PeQD stability is significantly critical for their application.

Highlights

Organic-inorganic hybrid lead halide perovskite ABX3 (A = MA; methylammonium, FA; formamidinium, B = Pb, X = Cl, Br, I) quantum dots (PeQDs) have greatly attracted attention as a light source for optoelectrical applications carrying the generation such as displays for remote medicine [1], photodetectors [2], and photovoltaics [3]. This is due to their excellent optical properties such as high photoluminescence quantum yields (PLQYs; over 70%), a narrow full width at half maximum (FWHM; 25 nm or less), and color tunability adjusted by the halide components in an entire tunability
QDs, they were measured by transmission electron microscope (TEM) and X-ray diffraction (XRD) analysis
To investigate the difference in the morphologies between MAPbBr3 and Mn/MAPbBr3 QDs, they were measured by TEM and XRD analysis

Summary

Introduction

Organic-inorganic hybrid lead halide perovskite ABX3 (A = MA; methylammonium, FA; formamidinium, B = Pb, X = Cl, Br, I) quantum dots (PeQDs) have greatly attracted attention as a light source for optoelectrical applications carrying the generation such as displays for remote medicine [1], photodetectors [2], and photovoltaics [3] This is due to their excellent optical properties such as high photoluminescence quantum yields (PLQYs; over 70%), a narrow full width at half maximum (FWHM; 25 nm or less), and color tunability adjusted by the halide components in an entire tunability Similar to the hot injection method, PeQDs prepared by the LARP method could be achieved

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Methods

Results

Conclusion