The chloride anion doped hybrid perovskite quantum dots exchanged by short surfactant ligand enable color-tunable blue fluorescent emitting for QLEDs application

Abstract

The facile approach combined the halide mixture of chloride and bromide anions with the exchange of short-chain ligand Phenethylamine (PEA) was used to prepare hybrid perovskite PEA-MAPbBr3-xClx quantum dots (PEA-QDs-Cl), which realized blue emissive quantum dots light-emitting diode (QLED) with wider gamut of Commission Internationale de l’Eclairage (CIE) coordinates (Δx = −0.04, Δy = 0.03) than National Television Systems Committee (NTSC) TV color standard. Compared to pristine MAPbBr3 quantum dots (pristine-QDs) prepared by conventional long-chain ligands, the size of PEA-QDs-Cl was manipulated from 9 nm to 3 nm characterized by HRTEM, emissive spectra were blue shifted from 528 nm to 469 nm measured by photoluminescence (PL). Meanwhile, time-resolved PL (TRPL) decay lifetimes of perovskite quantum dots doped with chloride anions (QDs-Cl) were improved from 10.3 ns to 13.9 ns, because short-chain ligands were introduced to passivate defects on the surface of QDs-Cl. Furthermore, XPS results showed that the chloride content was decreased from 34.7% to 33.7% through chloride vacancies on the surface of QDs-Cl were passivated by PEA.