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Title: Size Dependence of Doping by a Vacancy Formation Reaction in Copper Sulfide Nanocrystals

Abstract

Doping of nanocrystals (NCs) is a key, yet underexplored, approach for tuning of the electronic properties of semiconductors. An important route for doping of NCs is by vacancy formation. The size and concentration dependence of doping was studied in copper(I) sulfide (Cu2S) NCs through a redox reaction with iodine molecules (I2), which formed vacancies accompanied by a localized surface plasmon response. X-ray spectroscopy and diffraction reveal transformation from Cu2S to Cu-depleted phases, along with CuI formation. Greater reaction efficiency was observed for larger NCs. This behavior is attributed to interplay of the vacancy formation energy, which decreases for smaller sized NCs, and the growth of CuI on the NC surface, which is favored on well-defined facets of larger NCs. This doping process allows tuning of the plasmonic properties of a semiconductor across a wide range of plasmonic frequencies by varying the size of NCs and the concentration of iodine. Controlled vacancy doping of NCs may be used to tune and tailor semiconductors for use in optoelectronic applications.

Authors:
 [1];  [2];  [2];  [2]; ORCiD logo [1]
  1. The Institute of Chemistry and The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904 Israel
  2. Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook NY 11794 USA
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
National Science Foundation (NSF)
OSTI Identifier:
1377905
Resource Type:
Journal Article
Resource Relation:
Journal Name: Angewandte Chemie (International Edition); Journal Volume: 56; Journal Issue: 35
Country of Publication:
United States
Language:
ENGLISH
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 36 MATERIALS SCIENCE

Citation Formats

Elimelech, Orian, Liu, Jing, Plonka, Anna M., Frenkel, Anatoly I., and Banin, Uri. Size Dependence of Doping by a Vacancy Formation Reaction in Copper Sulfide Nanocrystals. United States: N. p., 2017. Web. doi:10.1002/anie.201702673.
Elimelech, Orian, Liu, Jing, Plonka, Anna M., Frenkel, Anatoly I., & Banin, Uri. Size Dependence of Doping by a Vacancy Formation Reaction in Copper Sulfide Nanocrystals. United States. doi:10.1002/anie.201702673.
Elimelech, Orian, Liu, Jing, Plonka, Anna M., Frenkel, Anatoly I., and Banin, Uri. 2017. "Size Dependence of Doping by a Vacancy Formation Reaction in Copper Sulfide Nanocrystals". United States. doi:10.1002/anie.201702673.
@article{osti_1377905,
title = {Size Dependence of Doping by a Vacancy Formation Reaction in Copper Sulfide Nanocrystals},
author = {Elimelech, Orian and Liu, Jing and Plonka, Anna M. and Frenkel, Anatoly I. and Banin, Uri},
abstractNote = {Doping of nanocrystals (NCs) is a key, yet underexplored, approach for tuning of the electronic properties of semiconductors. An important route for doping of NCs is by vacancy formation. The size and concentration dependence of doping was studied in copper(I) sulfide (Cu2S) NCs through a redox reaction with iodine molecules (I2), which formed vacancies accompanied by a localized surface plasmon response. X-ray spectroscopy and diffraction reveal transformation from Cu2S to Cu-depleted phases, along with CuI formation. Greater reaction efficiency was observed for larger NCs. This behavior is attributed to interplay of the vacancy formation energy, which decreases for smaller sized NCs, and the growth of CuI on the NC surface, which is favored on well-defined facets of larger NCs. This doping process allows tuning of the plasmonic properties of a semiconductor across a wide range of plasmonic frequencies by varying the size of NCs and the concentration of iodine. Controlled vacancy doping of NCs may be used to tune and tailor semiconductors for use in optoelectronic applications.},
doi = {10.1002/anie.201702673},
journal = {Angewandte Chemie (International Edition)},
number = 35,
volume = 56,
place = {United States},
year = 2017,
month = 7
}
  • Doping of nanocrystals (NCs) is a key, yet underexplored, approach for tuning of the electronic properties of semiconductors. An important route for doping of NCs is by vacancy formation. The size and concentration dependence of doping was studied in copper(I) sulfide (Cu2S) NCs through a redox reaction with iodine molecules (I2), which formed vacancies accompanied by a localized surface plasmon response. X-ray spectroscopy and diffraction reveal transformation from Cu2S to Cu-depleted phases, along with CuI formation. Greater reaction efficiency was observed for larger NCs. This behavior is attributed to interplay of the vacancy formation energy, which decreases for smaller sizedmore » NCs, and the growth of CuI on the NC surface, which is favored on well-defined facets of larger NCs. This doping process allows tuning of the plasmonic properties of a semiconductor across a wide range of plasmonic frequencies by varying the size of NCs and the concentration of iodine. Controlled vacancy doping of NCs may be used to tune and tailor semiconductors for use in optoelectronic applications.« less
  • Determination of the phase diagrams for the nanocrystalline forms of materials is crucial for our understanding of nanostructures and the design of functional materials using nanoscale building blocks. The ability to study such transformations in nanomaterials with controlled shape offers further insight into transition mechanisms and the influence of particular facets. Here we present an investigation of the size-dependent, temperature-induced solid-solid phase transition in copper sulfide nanorods from low- to high-chalcocite. We find the transition temperature to be substantially reduced, with the high chalcocite phase appearing in the smallest nanocrystals at temperatures so low that they are typical of photovoltaicmore » operation. Size dependence in phase trans- formations suggests the possibility of accessing morphologies that are not found in bulk solids at ambient conditions. These other- wise-inaccessible crystal phases could enable higher-performing materials in a range of applications, including sensing, switching, lighting, and photovoltaics.« less
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