Bright CsPbBr3 Perovskite Nanocrystals with Improved Stability by In-Situ Zn-Doping

Abstract

In this study, facile synthesis, characterization, and stability tests of highly luminescent Zn-doped CsPbBr3 perovskite nanocrystals (NCs) were demonstrated. The doping procedure was performed via partial replacement of PbBr2 with ZnBr2 in the precursor solution. Via Zn-doping, the photoluminescence quantum yield (PLQY) of the NCs was increased from 41.3% to 82.9%, with a blue-shifted peak at 503.7 nm and narrower spectral width of 18.7 nm which was consistent with the highly uniform size distribution of NCs observed from the TEM image. In the water-resistance stability test, the doped NCs exhibited an extended period-over four days until complete decomposition, under the harsh circumstances of hexane-ethanol-water mixing solution. The Zn-doped NC film maintained its 94% photoluminescence (PL) intensity after undergoing a heating/cooling cycle, surpassing the un-doped NC film with only 67% PL remaining. Based on our demonstrations, the in-situ Zn-doping procedure for the synthesis of CsPbBr3 NCs could be a promising strategy toward robust and PL-efficient nanomaterial to pave the way for realizing practical optoelectronic devices.

Improved exciton photoluminescence of Zn-doped quasi-2D perovskite nanocrystals and their application as luminescent materials in light-emitting devices

“…The significant enhancement of the PLQY can be attributed to the passivation of the Pb 2+ vacancy and the decreased defect density on the NC surface with the incorporation of Zn 2+ ions. 53 Time-resolved photoluminescence (TRPL) spectra of samples were recorded to further investigate the effect of Zn doping on the carrier recombination kinetics. As shown in Fig.…”

Origin of Excitonic Absorption in Multigrain CsPbBr3 Perovskite Nanocrystals: Implications in Photodiodes

“…The rotation of axis can be clearly observed in the fast Fourier transform (FFT) pattern shown in Figure f, which is the FFT image of the corresponding HRTEM image in Figure b. The small dark spots that appeared in Figure b were the structural defects caused by the electron irradiation-induced decomposition to PbBr 2 during HRTEM measurement. − We have not observed any nanocrystals with multiple grain boundaries in sample P1.…”

Synthesis of cesium lead bromide nanoparticles by the ultrasonic bath method: A polar-solvent-free approach at room temperature

“…In most literature reports, the PL decay curves of homogeneous CsPbBr 3 NCs were fit using a tri-exponential function that consisted of short-lived, mid-lived, and long-lived lifetime components. [34][35][36][37] The shortlived decay lifetime >1 ns can be attributed to the intrinsic exciton relaxation. 34 The mid-lived lifetime can be attributed to the interaction between the excitons and the phonons, whereas the long-lived lifetime corresponds to the interaction between…”