Growth Kinetics and Optical Properties of CsPbBr3 Perovskite Nanocrystals

Sung Kim,Hong Lee,Kyoung-Duck Park

doi:10.3390/en14020275

Sung Kim, Hong Lee + Show 1 more

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https://doi.org/10.3390/en14020275

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Abstract

We synthesized CsPbBr3 perovskite nanocrystals (NCs) at different reaction temperatures and tracked their growth kinetics on the basis of their optical properties and estimated size. The energies of the absorption and fluorescence (FL) peaks with increasing reaction temperature for the CsPbBr3 perovskite NCs were tuned within the regions of 2.429–2.570 eV and 2.391–2.469 eV, respectively, depending on size of the NCs (9.9–12.5 nm). The Stokes shifts of CsPbBr3 perovskite NCs with increasing NC size decreased from 101 meV to 38 meV. The full-width at half-maximum of the FL peaks for the CdSe NCs decreased from 150 meV to 90 meV because of the improved size uniformity of the CsPbBr3 perovskite NCs. The energy spacing of CsPbBr3 perovskite NCs synthesized at various reaction temperatures was calculated from Tauc plots; this information is critical for determining the bandgap energy and enables the size of the CsPbBr3 perovskite NCs to be estimated using the effective mass approximation.

Highlights

Lead halide perovskite nanocrystals (NCs) have inspired enormous interest in optoelectronics applications, such as light-emitting [1,2] and light-harvesting [3,4] devices and lasers [5], because of their tunable optical bandgaps through the precise engineering of halogen content and particle size [6]
We investigated the growth kinetics and optical properties of CsPbBr3 perovskite NCs with different reaction temperatures
The larger-sized perovskite NCs synthesized at the higher reaction temperature, which is a crucial factor to determine the morphology in the procedure of nucleation and growth of perovskite NCs, exhibit a smaller bandgap energy than that of the smaller-sized perovskite NCs [15]

Summary

Introduction

Lead halide perovskite nanocrystals (NCs) have inspired enormous interest in optoelectronics applications, such as light-emitting [1,2] and light-harvesting [3,4] devices and lasers [5], because of their tunable optical bandgaps through the precise engineering of halogen content and particle size [6]. Nanostructured lead halide perovskites exhibit interesting optical properties, such as narrow photoluminescence (PL) linewidths and high. Manipulating the defect concentration and size distribution of inorganic halide perovskite nanocrystals (IPNCs) is important for achieving narrow band emissions that improve color purity [8]. Amines enhance the crystallization kinetics, potentially enabling the size tuning of perovskite NCs, whereas oleic acid plays a critical role in impeding NC aggregation and leads to stable NC colloids [13]. Only a few studies have focused on the temperature dependence of the photophysical properties of all-inorganic perovskites [15]

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