You are here

Germanium-Tin/Cadmium Sulfide Core/Shell Nanocrystals with Enhanced Near-Infrared Photoluminescence

TitleGermanium-Tin/Cadmium Sulfide Core/Shell Nanocrystals with Enhanced Near-Infrared Photoluminescence
Publication TypeJournal Article
Year of Publication2017
AuthorsBoote, BW, Men, L, Andaraarachchi, HP, Bhattacharjee, U, Petrich, JW, Vela, J, Smith, EA
JournalChemistry of Materials
Volume29
Pagination6012-6021
Date Published07
Type of ArticleArticle
ISBN Number0897-4756
Accession NumberWOS:000406573200033
Keywordsalloy nanocrystals, chemistry, colloidal synthesis, energy-gap, ge nanocrystals, ge1-xsnx quantum dots, germanium, Materials Science, mesoporous, raman-spectroscopy, surface, tin, trichlorogermane-derived polymers
Abstract

Ge1-xSnx alloy nanocrystals and Ge1-xSnx/CdS core/shell nanocrystals were prepared via solution phase synthesis, and their size, composition, and optical properties were characterized. The diameter of the nanocrystal samples ranged from 6 to 13 nm. The crystal structure of the Ge1-xSnx materials was consistent with a cubic diamond phase, while the CdS shell was consistent with the zinc blende polytype. Inclusion of Sn alone does not result in enhanced photoluminescence intensity; however, adding an epitaxial CdS shell onto the Ge1-xSnx nanocrystals does enhance the photoluminescence up to 15-fold versus that of Ge/CdS nanocrystals with a pure Ge core. More effective passivation of surface defects, and a consequent decrease in the level of surface oxidation, by the CdS shell as a result of improved epitaxy (smaller lattice mismatch) is the most likely explanation for the increased photoluminescence observed for the Ge1-xSnx/CdS materials. With enhanced photoluminescence in the near-infrared region, Ge1-xSnx core/shell nanocrystals might be useful alternatives to other materials for energy capture and conversion applications and as imaging probes.

DOI10.1021/acs.chemmater.7b01815
Custom 1

Nanodomains