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Title: The effects of nanoparticles and organic additives with controlled dispersion on dielectric properties of polymers: Charge trapping and impact excitation

Abstract

This work presents a comprehensive investigation into the effects of nanoparticles and organic additives on the dielectric properties of insulating polymers using reinforced silicone rubber as a model system. TiO{sub 2} and ZrO{sub 2} nanoparticles (d = 5 nm) were well dispersed into the polymer via a bimodal surface modification approach. Organic molecules with the potential of voltage stabilization were further grafted to the nanoparticle to ensure their dispersion. These extrinsic species were found to provide deep traps for charge carriers and exhibited effective charge trapping properties at a rather small concentration (∼10{sup 17} cm{sup −3}). The charge trapping is found to have the most significant effect on breakdown strength when the electrical stressing time is long enough that most charges are trapped in the deep states. To establish a quantitative correlation between the trap depth and the molecular properties, the electron affinity and ionization energy of each species were calculated by an ab initio method and were compared with the experimentally measured values. The correlation however remains elusive and is possibly complicated by the field effect and the electronic interactions between different species that are not considered in this computation. At high field, a super-linear increase of current density was observed formore » TiO{sub 2} filled composites and is likely caused by impact excitation due to the low excitation energy of TiO{sub 2} compared to ZrO{sub 2}. It is reasoned that the hot charge carriers with energies greater than the excitation energy of TiO{sub 2} may excite an electron-hole pair upon collision with the NP, which later will be dissociated and contribute to free charge carriers. This mechanism can enhance the energy dissipation and may account for the retarded electrical degradation and breakdown of TiO{sub 2} composites.« less

Authors:
;  [1]; ; ; ;  [2]; ; ;  [3]
  1. Department of Material Science and Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)
  2. Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)
  3. Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208 (United States)
Publication Date:
OSTI Identifier:
22597741
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 5; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ADDITIVES; CALCULATION METHODS; CHARGE CARRIERS; COMPARATIVE EVALUATIONS; CONCENTRATION RATIO; CURRENT DENSITY; DIELECTRIC MATERIALS; DIELECTRIC PROPERTIES; DISPERSIONS; EFFECTIVE CHARGE; ELECTRONS; EXCITATION; NANOPARTICLES; RUBBERS; SILICONES; SURFACES; TITANIUM OXIDES; TRAPPING; ZIRCONIUM OXIDES

Citation Formats

Huang, Yanhui, E-mail: huangy12@rpi.edu, Schadler, Linda S., Wu, Ke, Ratcliff, Tyree, Lanzillo, Nicholas A., Breneman, Curt, Bell, Michael, Oakes, Andrew, and Benicewicz, Brian C. The effects of nanoparticles and organic additives with controlled dispersion on dielectric properties of polymers: Charge trapping and impact excitation. United States: N. p., 2016. Web. doi:10.1063/1.4959771.
Huang, Yanhui, E-mail: huangy12@rpi.edu, Schadler, Linda S., Wu, Ke, Ratcliff, Tyree, Lanzillo, Nicholas A., Breneman, Curt, Bell, Michael, Oakes, Andrew, & Benicewicz, Brian C. The effects of nanoparticles and organic additives with controlled dispersion on dielectric properties of polymers: Charge trapping and impact excitation. United States. doi:10.1063/1.4959771.
Huang, Yanhui, E-mail: huangy12@rpi.edu, Schadler, Linda S., Wu, Ke, Ratcliff, Tyree, Lanzillo, Nicholas A., Breneman, Curt, Bell, Michael, Oakes, Andrew, and Benicewicz, Brian C. Sun . "The effects of nanoparticles and organic additives with controlled dispersion on dielectric properties of polymers: Charge trapping and impact excitation". United States. doi:10.1063/1.4959771.
@article{osti_22597741,
title = {The effects of nanoparticles and organic additives with controlled dispersion on dielectric properties of polymers: Charge trapping and impact excitation},
author = {Huang, Yanhui, E-mail: huangy12@rpi.edu and Schadler, Linda S. and Wu, Ke and Ratcliff, Tyree and Lanzillo, Nicholas A. and Breneman, Curt and Bell, Michael and Oakes, Andrew and Benicewicz, Brian C.},
abstractNote = {This work presents a comprehensive investigation into the effects of nanoparticles and organic additives on the dielectric properties of insulating polymers using reinforced silicone rubber as a model system. TiO{sub 2} and ZrO{sub 2} nanoparticles (d = 5 nm) were well dispersed into the polymer via a bimodal surface modification approach. Organic molecules with the potential of voltage stabilization were further grafted to the nanoparticle to ensure their dispersion. These extrinsic species were found to provide deep traps for charge carriers and exhibited effective charge trapping properties at a rather small concentration (∼10{sup 17} cm{sup −3}). The charge trapping is found to have the most significant effect on breakdown strength when the electrical stressing time is long enough that most charges are trapped in the deep states. To establish a quantitative correlation between the trap depth and the molecular properties, the electron affinity and ionization energy of each species were calculated by an ab initio method and were compared with the experimentally measured values. The correlation however remains elusive and is possibly complicated by the field effect and the electronic interactions between different species that are not considered in this computation. At high field, a super-linear increase of current density was observed for TiO{sub 2} filled composites and is likely caused by impact excitation due to the low excitation energy of TiO{sub 2} compared to ZrO{sub 2}. It is reasoned that the hot charge carriers with energies greater than the excitation energy of TiO{sub 2} may excite an electron-hole pair upon collision with the NP, which later will be dissociated and contribute to free charge carriers. This mechanism can enhance the energy dissipation and may account for the retarded electrical degradation and breakdown of TiO{sub 2} composites.},
doi = {10.1063/1.4959771},
journal = {Journal of Applied Physics},
number = 5,
volume = 120,
place = {United States},
year = {Sun Aug 07 00:00:00 EDT 2016},
month = {Sun Aug 07 00:00:00 EDT 2016}
}
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