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Identifying and Eliminating Emissive Sub-bandgap States in Thin Films of PbS Nanocrystals.

ABSTRACT: Chemical oxidation of under-charged Pb atoms reduces the density of trap states by a factor of 40 in films of colloidal PbS quantum dots for devices. These emissive sub-bandgap states are a byproduct of several standard ligand-exchange procedures. X-ray photoelectron spectro-scopy measurements and density function theory simulations demonstrate that they are associated with under-charged Pb.

SUBMITTER: Hwang GW

PROVIDER: S-EPMC4755932 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Identifying and Eliminating Emissive Sub-bandgap States in Thin Films of PbS Nanocrystals.

Hwang Gyu Weon GW Kim Donghun D Cordero Jose M JM Wilson Mark W B MWB Chuang Chia-Hao M CM Grossman Jeffrey C JC Bawendi Moungi G MG

Advanced materials (Deerfield Beach, Fla.) 20150701 30

Chemical oxidation of under-charged Pb atoms reduces the density of trap states by a factor of 40 in films of colloidal PbS quantum dots for devices. These emissive sub-bandgap states are a byproduct of several standard ligand-exchange procedures. X-ray photoelectron spectro-scopy measurements and density function theory simulations demonstrate that they are associated with under-charged Pb. ...[more]

PMID: 26134373

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