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Observation of compositional domains within individual copper indium sulfide quantum dots.

ABSTRACT: The origin of photoluminescence in copper indium sulfide (CIS) quantum dots (Qdots) has previously been ascribed to a donor-acceptor pair (DAP) recombination, with a crystal lattice defect implicated as the origin of the donor state. In this study, electron energy-loss spectroscopy (EELS) was used to observe defect-rich compositional domains within individual CIS Qdots, supporting a model of defect-state-mediated photoluminescence for these particles, and identifying them as an ideal model system for future study of lattice defects on Qdot properties.

SUBMITTER: Harvie AJ

PROVIDER: S-EPMC5048650 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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Observation of compositional domains within individual copper indium sulfide quantum dots.

Harvie Andrew J AJ Booth Matthew M Chantry Ruth L RL Hondow Nicole N Kepaptsoglou Demie M DM Ramasse Quentin M QM Evans Stephen D SD Critchley Kevin K

Nanoscale 20160728 36

The origin of photoluminescence in copper indium sulfide (CIS) quantum dots (Qdots) has previously been ascribed to a donor-acceptor pair (DAP) recombination, with a crystal lattice defect implicated as the origin of the donor state. In this study, electron energy-loss spectroscopy (EELS) was used to observe defect-rich compositional domains within individual CIS Qdots, supporting a model of defect-state-mediated photoluminescence for these particles, and identifying them as an ideal model syste ...[more]

PMID: 27465708

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