Substrate effect on nanoporous structure of silica wires by channel-confined self-assembly of block-copolymer and sol-gel precursors

Hu, Michael Z.; Lai, Peng

doi:10.3934/matersci.2015.4.346

Title: Substrate effect on nanoporous structure of silica wires by channel-confined self-assembly of block-copolymer and sol-gel precursors

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Abstract

Nanoporous silica wires of various wire diameters were developed by space-confined molecular self-assembly of triblock copolymer ethylene/propylene/ethylene (P123) and silica alkoxide precursor (tetraethylorthosilicate, TEOS). Two distinctive hard-templating substrates, anodized aluminum oxide (AAO) and track-etched polycarbonate (EPC), with channel diameters in the range between 10 nm and 200 nm were employed for space-confinement of soft molecular self-assembly driven by the block-copolymer microphase separation. It was observed in the scanning and transmission electron microscope (STEM) studies that the substrate geometry and material characteristics had pronounced effects on the structure and morphology of the silica nanowires. A substrate wall effect was proposed to explain the ordering and orientation of the intra-wire mesostructure. Circular and spiral nanostructures were found only in wires formed in AAO substrate, not in EPC. Pore-size differences and distinctive wall morphologies of the nanowires relating to the substrates were discussed. It was shown that the material and channel wall characteristics of different substrates play key roles in the ordering and morphology of the intra-wire nanostructures.

Authors:

Hu, Michael Z. ^[1]; Lai, Peng ^[1]

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Publication Date:: Tue Sep 22 00:00:00 EDT 2015

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). High Temperature Materials Lab. (HTML)

Sponsoring Org.:: USDOE Office of Energy Efficiency and Renewable Energy (EERE)

OSTI Identifier:: 1215596

Grant/Contract Number:: AC05-00OR22725

Resource Type:: Accepted Manuscript

Journal Name:: AIMS Materials Science (Online)

Additional Journal Information:: Journal Name: AIMS Materials Science (Online); Journal Volume: 2; Journal Issue: 4; Journal ID: ISSN 2372-0484

Publisher:: AIMS Press

Country of Publication:: United States

Language:: English

Subject:: nanowires; mesoporous wires; self-assembly of block-copolymers

Citation Formats


                    Hu, Michael Z., and Lai, Peng. Substrate effect on nanoporous structure of silica wires by channel-confined self-assembly of block-copolymer and sol-gel precursors.  United States: N. p., 2015. 
Web.  doi:10.3934/matersci.2015.4.346.

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                    Hu, Michael Z., & Lai, Peng. Substrate effect on nanoporous structure of silica wires by channel-confined self-assembly of block-copolymer and sol-gel precursors.  United States.  https://doi.org/10.3934/matersci.2015.4.346

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                    Hu, Michael Z., and Lai, Peng. Tue .  
"Substrate effect on nanoporous structure of silica wires by channel-confined self-assembly of block-copolymer and sol-gel precursors".  United States.  https://doi.org/10.3934/matersci.2015.4.346.  https://www.osti.gov/servlets/purl/1215596.

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@article{osti_1215596,

  title        = {Substrate effect on nanoporous structure of silica wires by channel-confined self-assembly of block-copolymer and sol-gel precursors},

  author       = {Hu, Michael Z. and Lai, Peng},

  abstractNote = {Nanoporous silica wires of various wire diameters were developed by space-confined molecular self-assembly of triblock copolymer ethylene/propylene/ethylene (P123) and silica alkoxide precursor (tetraethylorthosilicate, TEOS). Two distinctive hard-templating substrates, anodized aluminum oxide (AAO) and track-etched polycarbonate (EPC), with channel diameters in the range between 10 nm and 200 nm were employed for space-confinement of soft molecular self-assembly driven by the block-copolymer microphase separation. It was observed in the scanning and transmission electron microscope (STEM) studies that the substrate geometry and material characteristics had pronounced effects on the structure and morphology of the silica nanowires. A substrate wall effect was proposed to explain the ordering and orientation of the intra-wire mesostructure. Circular and spiral nanostructures were found only in wires formed in AAO substrate, not in EPC. Pore-size differences and distinctive wall morphologies of the nanowires relating to the substrates were discussed. It was shown that the material and channel wall characteristics of different substrates play key roles in the ordering and morphology of the intra-wire nanostructures.},

  doi          = {10.3934/matersci.2015.4.346},

  journal      = {AIMS Materials Science (Online)},

  number       = 4,

  volume       = 2,

  place        = {United States},

  year         = {Tue Sep 22 00:00:00 EDT 2015},

  month        = {Tue Sep 22 00:00:00 EDT 2015}

}

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