High-Quality All-Inorganic Perovskite CsPbBr3 Quantum Dots Emitter Prepared by a Simple Purified Method and Applications of Light-Emitting Diodes

Tien Tien,Lin Lin,Tseng Tseng,Lee Lee,Dong Dong,Chen Chen

doi:10.3390/en12183507

Abstract

High-quality perovskite CsPbBr3 quantum dots (QDs-CsPbBr3) were prepared using the ultrasonic oscillation method, which is simple and provides variable yield according to requirements. The emission spectra over a large portion of the visible spectral region (450–650 nm) of QD-CsPbX3 (X = Cl, Br, and I) have tunable compositions that can be halide exchanged using the halide anion exchange technique and quantum size-effects. A strong peak with high intensity of (200) lattice plane of purified QDs-CsPbBr3 film is obtained, confirming the formation of an orthorhombic perovskite crystal structure of the Pnma space group. The photoluminescence of QDs-CsPbBr3 was characterized using a narrow line-width emission of 20 nm, with high quantum yields of up to 99.2%, and radioactive lifetime increasing to 26 ns. Finally, through the excellent advantages of QDs-CsPbBr3 mentioned above, purified perovskite QDs-CsPbBr3 as an active layer was utilized in perovskite quantum dot light-emitting diodes structure applications. As a result, the perovskite QDs-CsPbBr3 light-emitting diodes (LEDs) exhibits a turn-on voltage of 7 V and a maximum luminance of 5.1 cd/m2.

Highlights

All-inorganic cesium lead halide perovskite colloidal quantum dots (QDs-CsPbX3, X = Cl, Br, I)possess excellent optical properties such as broadband absorption, high photoluminescence quantum yield (PLQY) of 50–90%, narrow emission bandwidth of 12–42 nm, tunable emission wavelength of 400–700 nm, as well as a wide color gamut of about 110% national television system committee (NTSC) [1,2,3,4,5,6,7,8]
High-yield, high-crystallinity QDs-CsPbX3 (X = Cl, Br, I) can be obtained using the high-temperature hot injection method, they need to be synthesized in an inert atmosphere with temperatures of about 140–160 ◦ C
We investigate the material and optical properties of unpurified and purified QDs-CsPbBr3 via a purification procedure

Summary

Introduction

Possess excellent optical properties such as broadband absorption, high photoluminescence quantum yield (PLQY) of 50–90%, narrow emission bandwidth of 12–42 nm (from blue to red), tunable emission wavelength of 400–700 nm, as well as a wide color gamut of about 110% national television system committee (NTSC) [1,2,3,4,5,6,7,8].

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Conclusion