Toward Bright Colloidal Near-Infrared Emitters

Surface Passivation of 2D PbSe Nanoplatelets by Metal Halides

authored by: Leon Biesterfeld, Lars F. Klepzig, André Niebur, Marina Rosebrock, Jannika Lauth
Abstract: Colloidal 2D PbSe nanoplatelets (NPLs) are promising near- and short wave-infrared emitters for optoelectronic applications at telecommunication wavelengths. However, their photoluminescence quantum yield (PLQY) is limited by the ubiquitous presence of surface-related trap states. Here, we apply a treatment of colloidal PbSe NPLs with different metal halides (MX₂, M = Zn, Cd, Pb; X = F, Cl, Br, I) to improve their emission brightness. A surface passivation of the NPLs by PbI₂leads to the best results with a strongly increased PLQY (27% for PbSe NPLs emitting at 0.98 eV (1265 nm) and up to 61% for PbSe NPLs emitting at 1.25 eV (989 nm)). Simultaneously, the full width at half-maximum of the NPL photoluminescence decreased by 10% after the treatment. X-ray photoelectron spectroscopy and complementary surface treatment of PbSe NPLs with organic halides reveal the combined passivating role of both X-type binding halides X^-and Z-type binding metal halides MX₂in enhancing the optical properties of the PbSe NPLs. Our results emphasize the potential of 2D PbSe NPLs for efficient emission tailored for the application in fiber optics.
Organisation(s): PhoenixD: Photonics, Optics, and Engineering - Innovation Across Disciplines
Institute of Physical Chemistry and Electrochemistry
External Organisation(s): University of Tübingen
Type: Article
Journal: Journal of Physical Chemistry C
Volume: 126
Pages: 19277-19285
No. of pages: 9
ISSN: 1932-7447
Publication date: 17.11.2022
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Electronic, Optical and Magnetic Materials, Energy(all), Physical and Theoretical Chemistry, Surfaces, Coatings and Films
Electronic version(s): https://doi.org/10.1021/acs.jpcc.2c05850 (Access: Closed)