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Title: Thermal conductivity studies of metal dispersed multiwalled carbon nanotubes in water and ethylene glycol based nanofluids

Abstract

High thermal conducting metal nanoparticles have been dispersed on the multiwalled carbon nanotubes (MWNTs) outer surface. Structural and morphological characterizations of metal dispersed MWNTs have been carried out using x-ray diffraction analysis, high resolution transmission electron microscopy, energy dispersive x-ray analysis, and Fourier transform infrared spectroscopy. Nanofluids have been synthesized using metal-MWNTs in de-ionized water (DI water) and ethylene glycol (EG) base fluids. It has been observed that nanofluids maintain the same sequence of thermal conductivity as that of metal nanoparticles Ag-MWNTs>Au-MWNTs>Pd-MWNTs. A maximum enhancement of 37.3% and 11.3% in thermal conductivity has been obtained in Ag-MWNTs nanofluid with DI water and EG as base fluids, respectively, at a volume fraction of 0.03%. Temperature dependence study also shows enhancement of thermal conductivity with temperature.

Authors:
;  [1]
  1. Department of Physics, Alternative Energy and Nanotechnology Laboratory (AENL), Nano Functional Materials Technology Centre (NFMTC), Indian Institute of Technology Madras, Chennai 600036 (India)
Publication Date:
OSTI Identifier:
21361891
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 106; Journal Issue: 8; Other Information: DOI: 10.1063/1.3240307; (c) 2009 American Institute of Physics
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; CARBON; CHEMICAL ANALYSIS; FOURIER TRANSFORM SPECTROMETERS; FOURIER TRANSFORMATION; GLYCOLS; GOLD; INFRARED SPECTRA; NANOTUBES; PALLADIUM; PARTICLES; SILVER; TEMPERATURE DEPENDENCE; THERMAL CONDUCTIVITY; TRANSMISSION ELECTRON MICROSCOPY; WATER; X RADIATION; X-RAY DIFFRACTION; ALCOHOLS; COHERENT SCATTERING; DIFFRACTION; ELECTROMAGNETIC RADIATION; ELECTRON MICROSCOPY; ELEMENTS; HYDROGEN COMPOUNDS; HYDROXY COMPOUNDS; INTEGRAL TRANSFORMATIONS; IONIZING RADIATIONS; MEASURING INSTRUMENTS; METALS; MICROSCOPY; NANOSTRUCTURES; NONMETALS; ORGANIC COMPOUNDS; OXYGEN COMPOUNDS; PHYSICAL PROPERTIES; PLATINUM METALS; RADIATIONS; SCATTERING; SPECTRA; SPECTROMETERS; THERMODYNAMIC PROPERTIES; TRANSFORMATIONS; TRANSITION ELEMENTS

Citation Formats

Jha, Neetu, and Ramaprabhu, S. Thermal conductivity studies of metal dispersed multiwalled carbon nanotubes in water and ethylene glycol based nanofluids. United States: N. p., 2009. Web. doi:10.1063/1.3240307.
Jha, Neetu, & Ramaprabhu, S. Thermal conductivity studies of metal dispersed multiwalled carbon nanotubes in water and ethylene glycol based nanofluids. United States. doi:10.1063/1.3240307.
Jha, Neetu, and Ramaprabhu, S. 2009. "Thermal conductivity studies of metal dispersed multiwalled carbon nanotubes in water and ethylene glycol based nanofluids". United States. doi:10.1063/1.3240307.
@article{osti_21361891,
title = {Thermal conductivity studies of metal dispersed multiwalled carbon nanotubes in water and ethylene glycol based nanofluids},
author = {Jha, Neetu and Ramaprabhu, S.},
abstractNote = {High thermal conducting metal nanoparticles have been dispersed on the multiwalled carbon nanotubes (MWNTs) outer surface. Structural and morphological characterizations of metal dispersed MWNTs have been carried out using x-ray diffraction analysis, high resolution transmission electron microscopy, energy dispersive x-ray analysis, and Fourier transform infrared spectroscopy. Nanofluids have been synthesized using metal-MWNTs in de-ionized water (DI water) and ethylene glycol (EG) base fluids. It has been observed that nanofluids maintain the same sequence of thermal conductivity as that of metal nanoparticles Ag-MWNTs>Au-MWNTs>Pd-MWNTs. A maximum enhancement of 37.3% and 11.3% in thermal conductivity has been obtained in Ag-MWNTs nanofluid with DI water and EG as base fluids, respectively, at a volume fraction of 0.03%. Temperature dependence study also shows enhancement of thermal conductivity with temperature.},
doi = {10.1063/1.3240307},
journal = {Journal of Applied Physics},
number = 8,
volume = 106,
place = {United States},
year = 2009,
month =
}
  • In the present work, the temperature and concentration dependence of thermal conductivity (TC) enhancement in ethylene glycol (EG)-based amorphous and crystalline Al{sub 2}O{sub 3} nanofluids have been investigated at temperatures ranging from 0 to 100 °C. In our prior study, nanometer-sized particles of amorphous-, γ-, and α-Al{sub 2}O{sub 3} were prepared via a simple sol-gel process with annealing at different temperatures and characterized by various techniques. Building upon the earlier study, we probe here the crystallinity, microstructure, and morphology of the obtained α-Al{sub 2}O{sub 3} nanoparticles (NPs) by using X-ray powder diffraction with Rietveld full-profile refinement, scanning electron microscopy, and high-resolutionmore » transmission electron microscopy, respectively. In this study, we achieved a 74% enhancement in TC at higher temperature (100 °C) of base fluid EG by incorporating 1.0 vol. % of amorphous-Al{sub 2}O{sub 3}, whereas 52% and 37% enhancement is accomplished by adding γ- and α-Al{sub 2}O{sub 3} NPs, respectively. The amorphous phase of NPs appears to have good TC enhancement in nanofluids as compared to crystalline Al{sub 2}O{sub 3}. In a nutshell, these results are demonstrating the potential consequences of Al{sub 2}O{sub 3} NPs for applications of next-generation efficient energy transfer in nanofluids.« less
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