TY - JOUR

T1 - Colloidal 2D PbSe nanoplatelets with efficient emission reaching the telecom O-, E- and S-band

AU - Klepzig, Lars F.

AU - Biesterfeld, Leon

AU - Romain, Michel

AU - Niebur, André

AU - Schlosser, Anja

AU - Hübner, Jens

AU - Lauth, Jannika

N1 - Funding Information: J. H. gratefully acknowledges nancial support by the Deutsche Forschungsgemeinscha (DFG, German Research Foundation) under Germany's Excellence Strategy -EXC-2123 Quantum-Frontiers - 390837967 and HU 1318/4-1. L. K., L. B. and J. L. gratefully acknowledge funding by the Deutsche Forschungsgemeinscha (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. The authors thank the Laboratory for Nano and Quantum Engineering (LNQE) in Hannover for access to the TEM. We thank Nadja C. Bigall for access to the photoluminescence spectrometer and Dirk Dorfs for access to the UV-Vis-NIR absorption spectrometer. We are grateful to Armin Feldhoff for providing the XRD facilities.

PY - 2022/2

Y1 - 2022/2

N2 - Colloidal two-dimensional (2D) lead chalcogenide nanoplatelets (NPLs) represent highly interesting materials for near- and short wave-infrared applications including innovative glass fiber optics exhibiting negligible attenuation. In this work, we demonstrate a direct synthesis route for 2D PbSe NPLs with cubic rock salt crystal structure at low reaction temperatures of 0 °C and room temperature. A lateral size tuning of the PbSe NPLs by controlling the temperature and by adding small amounts of octylamine to the reaction leads to excitonic absorption features in the range of 1.55-1.24 eV (800-1000 nm) and narrow photoluminescence (PL) reaching the telecom O-, E- and S-band (1.38-0.86 eV, 900-1450 nm). The PL quantum yield of the as-synthesized PbSe NPLs is more than doubled by a postsynthetic treatment with CdCl2 (e.g. from 14.7% to 37.4% for NPLs emitting at 980 nm with a FWHM of 214 meV). An analysis of the slightly asymmetric PL line shape of the PbSe NPLs and their characterization by ultrafast transient absorption and time-resolved PL spectroscopy reveal a surface trap related PL contribution which is successfully reduced by the CdCl2 treatment from 40% down to 15%. Our results open up new pathways for a direct synthesis and straightforward incorporation of colloidal PbSe NPLs as efficient infrared emitters at technologically relevant telecom wavelengths.

AB - Colloidal two-dimensional (2D) lead chalcogenide nanoplatelets (NPLs) represent highly interesting materials for near- and short wave-infrared applications including innovative glass fiber optics exhibiting negligible attenuation. In this work, we demonstrate a direct synthesis route for 2D PbSe NPLs with cubic rock salt crystal structure at low reaction temperatures of 0 °C and room temperature. A lateral size tuning of the PbSe NPLs by controlling the temperature and by adding small amounts of octylamine to the reaction leads to excitonic absorption features in the range of 1.55-1.24 eV (800-1000 nm) and narrow photoluminescence (PL) reaching the telecom O-, E- and S-band (1.38-0.86 eV, 900-1450 nm). The PL quantum yield of the as-synthesized PbSe NPLs is more than doubled by a postsynthetic treatment with CdCl2 (e.g. from 14.7% to 37.4% for NPLs emitting at 980 nm with a FWHM of 214 meV). An analysis of the slightly asymmetric PL line shape of the PbSe NPLs and their characterization by ultrafast transient absorption and time-resolved PL spectroscopy reveal a surface trap related PL contribution which is successfully reduced by the CdCl2 treatment from 40% down to 15%. Our results open up new pathways for a direct synthesis and straightforward incorporation of colloidal PbSe NPLs as efficient infrared emitters at technologically relevant telecom wavelengths.

UR - http://www.scopus.com/inward/record.url?scp=85123933447&partnerID=8YFLogxK

U2 - 10.1039/d1na00704a

DO - 10.1039/d1na00704a

M3 - Article

VL - 4

SP - 590

EP - 599

JO - Nanoscale Advances

JF - Nanoscale Advances

IS - 2

ER -