Journal Article

IMPULSE-2019-00180

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Boosting Tunable Blue Luminescence of Halide Perovskite Nanoplatelets through Postsynthetic Surface Trap Repair

Bohn, B. J. ; Tong, Y. ; Gramlich, M. ; Lai, M. L. ; Döblinger, M. ; Wang, K. ; Hoye, R. L. Z. ; Müller-Buschbaum, P.MLZ* ; Stranks, S. D. ; Urban, A. S. ; Polavarapu, L. ; Feldmann, J.

2018
ACS Publ. Washington, DC

Please use a persistent id in citations: doi:10.1021/acs.nanolett.8b02190

Abstract: The easily tunable emission of halide perovskite nanocrystals throughout the visible spectrum makes them an extremely promising material for light-emitting applications. Whereas high quantum yields and long-term colloidal stability have already been achieved for nanocrystals emitting in the red and green spectral range, the blue region currently lags behind with low quantum yields, broad emission profiles, and insufficient colloidal stability. In this work, we present a facile synthetic approach for obtaining two-dimensional CsPbBr3 nanoplatelets with monolayer-precise control over their thickness, resulting in sharp photoluminescence and electroluminescence peaks with a tunable emission wavelength between 432 and 497 nm due to quantum confinement. Subsequent addition of a PbBr2-ligand solution repairs surface defects likely stemming from bromide and lead vacancies in a subensemble of weakly emissive nanoplatelets. The overall photoluminescence quantum yield of the blue-emissive colloidal dispersions is consequently enhanced up to a value of 73 ± 2%. Transient optical spectroscopy measurements focusing on the excitonic resonances further confirm the proposed repair process. Additionally, the high stability of these nanoplatelets in films and to prolonged ultraviolet light exposure is shown.

Keyword(s): Energy (1st) ; Chemistry (2nd) ; Materials Science (2nd)

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Contributing Institute(s):

1. E13

Experiment(s):

1. No specific instrument

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Database coverage:
; Clarivate Analytics Master Journal List ; Current Contents - Physical, Chemical and Earth Sciences ; Ebsco Academic Search ; IF >= 10 ; JCR ; NCBI Molecular Biology Database ; SCOPUS ; Science Citation Index ; Science Citation Index Expanded ; Web of Science Core Collection

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