TY - JOUR

T1 - Toward Bright Colloidal Near-Infrared Emitters

T2 - Surface Passivation of 2D PbSe Nanoplatelets by Metal Halides

AU - Biesterfeld, Leon

AU - Klepzig, Lars F.

AU - Niebur, André

AU - Rosebrock, Marina

AU - Lauth, Jannika

N1 - Funding Information: The authors thank the Laboratory for Nano and Quantum Engineering (LNQE) in Hannover for access to the TEM. We thank N. C. Bigall for access to the UV–vis–NIR photoluminescence spectrometer, the XPS (major equipment DFG Project 448713396), and D. Dorfs for access to the UV–vis–NIR absorption spectrometer. We are grateful to A. Feldhoff for providing the XRD facilities and to J. Caro for access to the ATR-FTIR spectrometer. L.B., L.F.K., and J.L. gratefully acknowledge funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy within the Cluster of Excellence PhoenixD (EXC 2122, Project ID 390833453). J.L. is thankful for additional funding by the Caroline Herschel program of the Leibniz Universität Hannover.

PY - 2022/11/17

Y1 - 2022/11/17

N2 - 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.

AB - 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.

UR - http://www.scopus.com/inward/record.url?scp=85141771019&partnerID=8YFLogxK

U2 - 10.1021/acs.jpcc.2c05850

DO - 10.1021/acs.jpcc.2c05850

M3 - Article

AN - SCOPUS:85141771019

VL - 126

SP - 19277

EP - 19285

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 45

ER -