Campus Units

Chemistry, Ames Laboratory

Document Type

Article

Publication Version

Accepted Manuscript

Publication Date

7-25-2017

Journal or Book Title

Chemistry of Materials

Volume

29

Issue

14

First Page

6012

Last Page

6021

DOI

10.1021/acs.chemmater.7b01815

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–xSnxnanocrystals 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.

Comments

This article is published as Boote, Brett W., Long Men, Himashi P. Andaraarachchi, Ujjal Bhattacharjee, Jacob W. Petrich, Javier Vela, and Emily A. Smith. "Germanium–Tin/Cadmium Sulfide Core/Shell Nanocrystals with Enhanced Near-Infrared Photoluminescence." Chemistry of Materials 29, no. 14 (2017): 6012-6021. DOI: 10.1021/acs.chemmater.7b01815. Posted with permission.

Copyright Owner

American Chemical Society

Language

en

File Format

application/pdf

Published Version

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