Origin of Amplified Spontaneous Emission Degradation in MAPbBr3 Thin Films under Nanosecond-UV Laser Irradiation

Maria Luisa De Giorgi,Nur Fadilah Jamaludin,Titti Lippolis,Marco Anni,Annalisa Bruno,Cesare Soci

doi:10.1021/acs.jpcc.0c02331

Maria Luisa De Giorgi, Nur Fadilah Jamaludin + Show 4 more

Open Access

https://doi.org/10.1021/acs.jpcc.0c02331

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Abstract

Hybrid halide perovskites have achieved excellent efficiencies and remarkable performances, not just in photovoltaic cells, but also in light-emitting devices, like Light Emitting Diodes, Light Emi...

Highlights

Hybrid metal−lead halide perovskites, such as MAPbX3, have recently emerged as an innovative class of photovoltaic materials with high efficiencies due to their large absorption coefficients, excellent charge mobilities, and high diffusion lengths.[1−11] Thanks to the combination of the above-mentioned outstanding properties and a low-cost deposition process from solution, inexpensive solar cells with certified power conversion efficiencies up to 25.2%12 have been realized
We have demonstrated that laser irradiation of MAPbBr3 thin films with nanosecond pulses at excitation densities higher than the amplified spontaneous emissions (ASE) threshold does not affect the spontaneous emission (SE), it can result in ASE degradation and local variations of both the film morphology and the PL intensity
At the highest used values of the average energy density, the energy absorbed by the material, which corresponds to the maximum intensity of the beam, is high enough to melt off the film

Summary

Introduction

By PL mapping and SEM, that the ASE degradation in a vacuum is mainly related to a variation in the film morphology in the region of the maximum pump intensity, leading to a localized PL quenching for excitation densities up to 3× the ASE threshold. In order to investigate the processes that cause the decrease in the ASE intensity and to explain the observed excitation densities and environment dependence, we investigated the effects of irradiation on the film morphology and the local emission properties by scanning electron and photoluminescence mapping microscopy (Figure 3) at the end of each irradiation cycle.

Results

Conclusion