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Title: Electrical conductivity of cellular Si/SiC ceramic composites prepared from plant precursors

Abstract

Electrical conductivity ({sigma}{sub dc}) of the cellular Si/SiC ceramic composites has been measured over a temperature range of 25-1073 K, while the thermoelectric power (S) has been measured over 25-300 K. Remarkably, these cellular compounds developed through the biomimetic route--where the ceramic system grows within a plant biotemplate retaining the imprint of structural intricacies of the native templates--are found to exhibit excellent mechanical, thermal, and electrical properties quite comparable to or even better than those of the systems prepared through the conventional ceramic route. The electrical conductivity, measured parallel ({sigma}{sub (parallel{sub sign})}) and perpendicular ({sigma}{sub (perpendicular{sub sign})}) to the growth axes of the native plants, depicts nearly temperature-independent anisotropy ({sigma}{sub (perpendicular{sub sign})})/{sigma}{sub (parallel{sub sign})}) of the order {approx}2, while the thermoelectric power is nearly isotropic. The charge conduction across the entire temperature regime is found to follow closely the variable range hopping mechanism. The conductivity anisotropy appears to be driven primarily by the unique microcellular morphology of the biotemplates, which can be exploited in many electrical applications.

Authors:
; ; ; ; ;  [1];  [2];  [2];  [2];  [2]
  1. Non-oxide Ceramics and Composites Division, Central Glass and Ceramic Research Institute, Kolkata 700 032 (India)
  2. (India)
Publication Date:
OSTI Identifier:
20982676
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 3; Other Information: DOI: 10.1063/1.2433137; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANISOTROPY; CERAMICS; CRYSTAL GROWTH; ELECTRIC CONDUCTIVITY; MORPHOLOGY; SEMICONDUCTOR MATERIALS; SILICON; SILICON CARBIDES; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0013-0065 K; TEMPERATURE RANGE 0065-0273 K; TEMPERATURE RANGE 0273-0400 K; TEMPERATURE RANGE 0400-1000 K; TEMPERATURE RANGE 1000-4000 K

Citation Formats

Mallick, Debopriyo, Chakrabarti, Omprakash, Bhattacharya, Dipten, Mukherjee, Manabendra, Maiti, Himadri S., Majumdar, Rabindranath, Electroceramics Division, Central Glass and Ceramic Research Institute, Kolkata 700 032, Surface Physics Division, Saha Institute of Nuclear Physics, Kolkata 700 064, Electroceramics Division, Central Glass and Ceramic Research Institute, Kolkata 700 032, and Department of Chemical Technology, University of Calcutta, Kolkata 700 009. Electrical conductivity of cellular Si/SiC ceramic composites prepared from plant precursors. United States: N. p., 2007. Web. doi:10.1063/1.2433137.
Mallick, Debopriyo, Chakrabarti, Omprakash, Bhattacharya, Dipten, Mukherjee, Manabendra, Maiti, Himadri S., Majumdar, Rabindranath, Electroceramics Division, Central Glass and Ceramic Research Institute, Kolkata 700 032, Surface Physics Division, Saha Institute of Nuclear Physics, Kolkata 700 064, Electroceramics Division, Central Glass and Ceramic Research Institute, Kolkata 700 032, & Department of Chemical Technology, University of Calcutta, Kolkata 700 009. Electrical conductivity of cellular Si/SiC ceramic composites prepared from plant precursors. United States. doi:10.1063/1.2433137.
Mallick, Debopriyo, Chakrabarti, Omprakash, Bhattacharya, Dipten, Mukherjee, Manabendra, Maiti, Himadri S., Majumdar, Rabindranath, Electroceramics Division, Central Glass and Ceramic Research Institute, Kolkata 700 032, Surface Physics Division, Saha Institute of Nuclear Physics, Kolkata 700 064, Electroceramics Division, Central Glass and Ceramic Research Institute, Kolkata 700 032, and Department of Chemical Technology, University of Calcutta, Kolkata 700 009. Thu . "Electrical conductivity of cellular Si/SiC ceramic composites prepared from plant precursors". United States. doi:10.1063/1.2433137.
@article{osti_20982676,
title = {Electrical conductivity of cellular Si/SiC ceramic composites prepared from plant precursors},
author = {Mallick, Debopriyo and Chakrabarti, Omprakash and Bhattacharya, Dipten and Mukherjee, Manabendra and Maiti, Himadri S. and Majumdar, Rabindranath and Electroceramics Division, Central Glass and Ceramic Research Institute, Kolkata 700 032 and Surface Physics Division, Saha Institute of Nuclear Physics, Kolkata 700 064 and Electroceramics Division, Central Glass and Ceramic Research Institute, Kolkata 700 032 and Department of Chemical Technology, University of Calcutta, Kolkata 700 009},
abstractNote = {Electrical conductivity ({sigma}{sub dc}) of the cellular Si/SiC ceramic composites has been measured over a temperature range of 25-1073 K, while the thermoelectric power (S) has been measured over 25-300 K. Remarkably, these cellular compounds developed through the biomimetic route--where the ceramic system grows within a plant biotemplate retaining the imprint of structural intricacies of the native templates--are found to exhibit excellent mechanical, thermal, and electrical properties quite comparable to or even better than those of the systems prepared through the conventional ceramic route. The electrical conductivity, measured parallel ({sigma}{sub (parallel{sub sign})}) and perpendicular ({sigma}{sub (perpendicular{sub sign})}) to the growth axes of the native plants, depicts nearly temperature-independent anisotropy ({sigma}{sub (perpendicular{sub sign})})/{sigma}{sub (parallel{sub sign})}) of the order {approx}2, while the thermoelectric power is nearly isotropic. The charge conduction across the entire temperature regime is found to follow closely the variable range hopping mechanism. The conductivity anisotropy appears to be driven primarily by the unique microcellular morphology of the biotemplates, which can be exploited in many electrical applications.},
doi = {10.1063/1.2433137},
journal = {Journal of Applied Physics},
number = 3,
volume = 101,
place = {United States},
year = {Thu Feb 01 00:00:00 EST 2007},
month = {Thu Feb 01 00:00:00 EST 2007}
}
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