Light Emission Properties of Thermally Evaporated CH3NH3PbBr3 Perovskite from Nano- to Macro-Scale: Role of Free and Localized Excitons

Over the past decade, interest about metal halide perovskites has rapidly increased, as they can find wide application in optoelectronic devices. Nevertheless, although thermal evaporation is crucial for the development and engineering of such devices based on multilayer structures, the optical prop...

Full description

Saved in:
Bibliographic Details
Published inNanomaterials (Basel, Switzerland) Vol. 12; no. 2; p. 211
Main Authors Triolo, Claudia, De Giorgi, Maria Luisa, Lorusso, Antonella, Cretì, Arianna, Santangelo, Saveria, Lomascolo, Mauro, Anni, Marco, Mazzeo, Marco, Patané, Salvatore
Format Journal Article
LanguageEnglish
Published Basel MDPI AG 10.01.2022
MDPI
Subjects
Amplification
Crystallites
Crystals
Emission analysis
Evaporation
Excitons
free excitons
Glass substrates
Lasers
Light emission
localized excitons
Metal halides
Microscopy
Morphology
Multilayers
Optical properties
Optoelectronic devices
perovskite
Perovskites
PL emission
Radiation
Species
Spontaneous emission
Stimulated emission
thermal evaporation
Thin films
trap states
Ultraviolet radiation
Online AccessGet full text

Cover

More Information
Summary:Over the past decade, interest about metal halide perovskites has rapidly increased, as they can find wide application in optoelectronic devices. Nevertheless, although thermal evaporation is crucial for the development and engineering of such devices based on multilayer structures, the optical properties of thermally deposited perovskite layers (spontaneous and amplified spontaneous emission) have been poorly investigated. This paper is a study from a nano- to micro- and macro-scale about the role of light-emitting species (namely free carriers and excitons) and trap states in the spontaneous emission of thermally evaporated thin layers of CH3NH3PbBr3 perovskite after wet air UV light trap passivation. The map of light emission from grains, carried out by SNOM at the nanoscale and by micro-PL techniques, clearly indicates that free and localized excitons (EXs) are the dominant light-emitting species, the localized excitons being the dominant ones in the presence of crystallites. These species also have a key role in the amplified spontaneous emission (ASE) process: for higher excitation densities, the relative contribution of localized EXs basically remains constant, while a clear competition between ASE and free EXs spontaneous emission is present, which suggests that ASE is due to stimulated emission from the free EXs.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
ISSN:2079-4991
2079-4991
DOI:10.3390/nano12020211