Size-Dependent Phonon-Assisted Anti-Stokes Photoluminescence in Nanocrystals of Organometal Perovskites.

Autor: Sekerbayev K; Institute of Experimental and Theoretical Physics, Al-Farabi Kazakh National University, Almaty 050040, Kazakhstan.; Department of Physics, School of Sciences and Humanities, Nazarbayev University, Nur-Sultan 010000, Kazakhstan., Taurbayev Y; Institute of Experimental and Theoretical Physics, Al-Farabi Kazakh National University, Almaty 050040, Kazakhstan., Mussabek G; Institute of Experimental and Theoretical Physics, Al-Farabi Kazakh National University, Almaty 050040, Kazakhstan.; Institute of Information and Computational Technologies, 125, Pushkin Str., Almaty 050000, Kazakhstan., Baktygerey S; Institute of Experimental and Theoretical Physics, Al-Farabi Kazakh National University, Almaty 050040, Kazakhstan.; Institute of Information and Computational Technologies, 125, Pushkin Str., Almaty 050000, Kazakhstan., Pokryshkin NS; Phys-Bio Institute, University 'MEPhI', 115409 Moscow, Russia.; Faculty of Physics, Lomonosov Moscow State University, 119991 Moscow, Russia., Yakunin VG; Faculty of Physics, Lomonosov Moscow State University, 119991 Moscow, Russia., Utegulov Z; Department of Physics, School of Sciences and Humanities, Nazarbayev University, Nur-Sultan 010000, Kazakhstan., Timoshenko VY; Faculty of Physics, Lomonosov Moscow State University, 119991 Moscow, Russia.
Jazyk: angličtina
Zdroj: Nanomaterials (Basel, Switzerland) [Nanomaterials (Basel)] 2022 Sep 14; Vol. 12 (18). Date of Electronic Publication: 2022 Sep 14.
DOI: 10.3390/nano12183184
Abstrakt: Anti-Stokes photoluminescence (ASPL), which is an up-conversion phonon-assisted process of the radiative recombination of photoexcited charge carriers, was investigated in methylammonium lead bromide (MALB) perovskite nanocrystals (NCs) with mean sizes that varied from about 6 to 120 nm. The structure properties of the MALB NCs were investigated by means of the scanning and transmission electron microscopy, X-ray diffraction and Raman spectroscopy. ASPL spectra of MALB NCs were measured under near-resonant laser excitation with a photon energy of 2.33 eV and they were compared with the results of the photoluminescence (PL) measurements under non-resonant excitation at 3.06 eV to reveal a contribution of phonon-assisted processes in ASPL. MALB NCs with a mean size of about 6 nm were found to demonstrate the most efficient ASPL, which is explained by an enhanced contribution of the phonon absorption process during the photoexcitation of small NCs. The obtained results can be useful for the application of nanocrystalline organometal perovskites in optoelectronic and all-optical solid-state cooling devices.
Databáze: MEDLINE