Morphology and Band Structure of Orthorhombic PbS Nanoplatelets: An Indirect Band Gap Material
نویسندگان
چکیده
PbS quantum dots and nanoplatelets (NPLs) are of enormous interest in the development optoelectronic devices. However, some important aspects their nature remain unclear. Recent studies have revealed that colloidal NPLs may depart from rock-salt crystal structure bulk form an orthorhombic (Pnma) modification instead. To gain insight into implications such a change over properties, we synthesized determined lattice parameters by means selected area electron diffraction measurements. We then calculated associated band using density functional theory with Perdew–Burke–Ernzerhof for solids GW approximation, including spin–orbit interactions. An indirect gap is found, which explain weak luminescence reported experiments. derive effective masses conduction valence bands deduce confinement along crystallographic axis (short NPL) reinforces but b c axes favors direct Calculations 1.8 nm thickness, carried out k·p theory, show excitonic effects strong, binding energies about 150 meV.
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ژورنال
عنوان ژورنال: Chemistry of Materials
سال: 2021
ISSN: ['1520-5002', '0897-4756']
DOI: https://doi.org/10.1021/acs.chemmater.0c04281