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Title: Chalcogenide and pnictide nanocrystals from the silylative deoxygenation of metal oxides

Abstract

Transition metal chalcogenide and pnictide nanocrystals are of interest for optoelectronic and catalytic applications. In this paper, we present a generalized route to the synthesis of these materials from the silylative deoxygenation of metal oxides with trimethylsilyl reagents. Specific nanophases produced in this way include Ni 3S 2, Ni 5Se 5, Ni 2P, Co 9S 8, Co 3Se 4, CoP, Co 2P, and heterobimetallic (Ni/Co) 9S 8. The resulting chalcogenide nanocrystals are hollow, likely due to differential rates of ion diffusion during the interfacial phase transformation reaction (Kirkendall-type effect). In contrast, the phosphide nanocrystals are solid, likely because they form at higher reaction temperatures. Finally, in all cases, simultaneous partial decomposition of the deoxygenating silyl reagent produces a coating of amorphous silica around the newly formed nanocrystals, which could impact their stability and recyclability.

Authors:
 [1];  [1]; ORCiD logo [2]
  1. Iowa State Univ., Ames, IA (United States). Dept. of Chemistry
  2. Iowa State Univ., Ames, IA (United States). Dept. of Chemistry; Ames Lab., Ames, IA (United States)
Publication Date:
Research Org.:
Ames Lab., Ames, IA (United States); Iowa State Univ., Ames, IA (United States)
Sponsoring Org.:
USDOE; National Science Foundation (NSF)
OSTI Identifier:
1407481
Report Number(s):
IS-J-9480
Journal ID: ISSN 2050-7488; TRN: US1703150
Grant/Contract Number:
AC02-07CH11358; 1253058
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Materials Chemistry. A
Additional Journal Information:
Journal Volume: 5; Journal Issue: 38; Journal ID: ISSN 2050-7488
Publisher:
Royal Society of Chemistry
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Lin, Chia-Cheng, Tan, Shannon J., and Vela, Javier. Chalcogenide and pnictide nanocrystals from the silylative deoxygenation of metal oxides. United States: N. p., 2017. Web. doi:10.1039/c7ta02581e.
Lin, Chia-Cheng, Tan, Shannon J., & Vela, Javier. Chalcogenide and pnictide nanocrystals from the silylative deoxygenation of metal oxides. United States. doi:10.1039/c7ta02581e.
Lin, Chia-Cheng, Tan, Shannon J., and Vela, Javier. Mon . "Chalcogenide and pnictide nanocrystals from the silylative deoxygenation of metal oxides". United States. doi:10.1039/c7ta02581e.
@article{osti_1407481,
title = {Chalcogenide and pnictide nanocrystals from the silylative deoxygenation of metal oxides},
author = {Lin, Chia-Cheng and Tan, Shannon J. and Vela, Javier},
abstractNote = {Transition metal chalcogenide and pnictide nanocrystals are of interest for optoelectronic and catalytic applications. In this paper, we present a generalized route to the synthesis of these materials from the silylative deoxygenation of metal oxides with trimethylsilyl reagents. Specific nanophases produced in this way include Ni3S2, Ni5Se5, Ni2P, Co9S8, Co3Se4, CoP, Co2P, and heterobimetallic (Ni/Co)9S8. The resulting chalcogenide nanocrystals are hollow, likely due to differential rates of ion diffusion during the interfacial phase transformation reaction (Kirkendall-type effect). In contrast, the phosphide nanocrystals are solid, likely because they form at higher reaction temperatures. Finally, in all cases, simultaneous partial decomposition of the deoxygenating silyl reagent produces a coating of amorphous silica around the newly formed nanocrystals, which could impact their stability and recyclability.},
doi = {10.1039/c7ta02581e},
journal = {Journal of Materials Chemistry. A},
number = 38,
volume = 5,
place = {United States},
year = {Mon Sep 11 00:00:00 EDT 2017},
month = {Mon Sep 11 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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