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Title: Calcination does not remove all carbon from colloidal nanocrystal assemblies

Abstract

Removing organics from hybrid nanostructures is a crucial step in many bottom-up materials fabrication approaches. It is usually assumed that calcination is an effective solution to this problem, especially for thin films. This assumption has led to its application in thousands of papers. Here in this paper, we show that this general assumption is incorrect by using a relevant and highly controlled model system consisting of thin films of ligand-capped ZrO2 nanocrystals. After calcination at 800 °C for 12 h, while Raman spectroscopy fails to detect the ligands after calcination, elastic backscattering spectrometry characterization demonstrates that ~18% of the original carbon atoms are still present in the film. By comparison plasma processing successfully removes the ligands. Our growth kinetic analysis shows that the calcined materials have significantly different interfacial properties than the plasma-processed counterparts. Calcination is not a reliable strategy for the production of single-phase all-inorganic materials from colloidal nanoparticles.

Authors:
 [1];  [1];  [2];  [2];  [3];  [4];  [5];  [1];  [2]; ORCiD logo [6]
  1. Iowa State Univ., Ames, IA (United States). Dept. of Materials Science & Engineering
  2. Iowa State Univ., Ames, IA (United States). Dept. of Chemistry; Ames Lab., Ames, IA (United States)
  3. Univ. de Sao Paulo, Sao Paulo (Brazil). Inst. de Fisica
  4. Univ. of Michigan, Ann Arbor, MI (United States). Michigan Ion Beam Lab.
  5. Iowa State Univ., Ames, IA (United States). Dept. of Chemical & Biological Engineering
  6. Iowa State Univ., Ames, IA (United States). Dept. of Materials Science & Engineering; Ames Lab., Ames, IA (United States); Iowa State Univ., Ames, IA (United States). Dept. of Chemical & Biological Engineering
Publication Date:
Research Org.:
Ames Laboratory (AMES), Ames, IA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
OSTI Identifier:
1415820
Report Number(s):
IS-J-9533
Journal ID: ISSN 2041-1723; PII: 2267
Grant/Contract Number:  
AC02-07CH11358
Resource Type:
Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal Issue: 1; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 77 NANOSCIENCE AND NANOTECHNOLOGY; Design, synthesis and processing; Nanoscale materials

Citation Formats

Mohapatra, Pratyasha, Shaw, Santosh, Mendivelso-Perez, Deyny, Bobbitt, Jonathan M., Silva, Tiago F., Naab, Fabian, Yuan, Bin, Tian, Xinchun, Smith, Emily A., and Cademartiri, Ludovico. Calcination does not remove all carbon from colloidal nanocrystal assemblies. United States: N. p., 2017. Web. doi:10.1038/s41467-017-02267-9.
Mohapatra, Pratyasha, Shaw, Santosh, Mendivelso-Perez, Deyny, Bobbitt, Jonathan M., Silva, Tiago F., Naab, Fabian, Yuan, Bin, Tian, Xinchun, Smith, Emily A., & Cademartiri, Ludovico. Calcination does not remove all carbon from colloidal nanocrystal assemblies. United States. https://doi.org/10.1038/s41467-017-02267-9
Mohapatra, Pratyasha, Shaw, Santosh, Mendivelso-Perez, Deyny, Bobbitt, Jonathan M., Silva, Tiago F., Naab, Fabian, Yuan, Bin, Tian, Xinchun, Smith, Emily A., and Cademartiri, Ludovico. Mon . "Calcination does not remove all carbon from colloidal nanocrystal assemblies". United States. https://doi.org/10.1038/s41467-017-02267-9. https://www.osti.gov/servlets/purl/1415820.
@article{osti_1415820,
title = {Calcination does not remove all carbon from colloidal nanocrystal assemblies},
author = {Mohapatra, Pratyasha and Shaw, Santosh and Mendivelso-Perez, Deyny and Bobbitt, Jonathan M. and Silva, Tiago F. and Naab, Fabian and Yuan, Bin and Tian, Xinchun and Smith, Emily A. and Cademartiri, Ludovico},
abstractNote = {Removing organics from hybrid nanostructures is a crucial step in many bottom-up materials fabrication approaches. It is usually assumed that calcination is an effective solution to this problem, especially for thin films. This assumption has led to its application in thousands of papers. Here in this paper, we show that this general assumption is incorrect by using a relevant and highly controlled model system consisting of thin films of ligand-capped ZrO2 nanocrystals. After calcination at 800 °C for 12 h, while Raman spectroscopy fails to detect the ligands after calcination, elastic backscattering spectrometry characterization demonstrates that ~18% of the original carbon atoms are still present in the film. By comparison plasma processing successfully removes the ligands. Our growth kinetic analysis shows that the calcined materials have significantly different interfacial properties than the plasma-processed counterparts. Calcination is not a reliable strategy for the production of single-phase all-inorganic materials from colloidal nanoparticles.},
doi = {10.1038/s41467-017-02267-9},
journal = {Nature Communications},
number = 1,
volume = 8,
place = {United States},
year = {Mon Dec 11 00:00:00 EST 2017},
month = {Mon Dec 11 00:00:00 EST 2017}
}

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