Δημοσιεύσεις

Project Acronym: AMONADE
Title: Atomistic MOdelling of NAnostructures and extended DEfects
Affiliation: aristotle university of thessaloniki
Pi: Joseph Kioseoglou
Research Field: physics

Enhanced thermal conductivity in percolating nanocomposites: a molecular dynamics investigation
by Termentzidis, Konstantinos, Giordano, Valentina M., Katsikini, Maria, Paloura, Eleni, Pernot, Gilles, Verdier, Maxime, Lacroix, David, Karakostas, Ioannis and Kioseoglou, Joseph
Abstract:
In this work we present a molecular dynamics investigation of thermal transport in a silica-gallium nitride nanocomposite. A surprising enhancement of the thermal conductivity for crystalline volume fractions larger than 5% is found, which cannot be predicted by an effective medium approach, not even including percolation effects, the model systematically leading to an underestimation of the effective thermal conductivity. The behavior can instead be reproduced if an effective volume fraction twice larger than the real one is assumed, which translates in a percolation effect surprisingly stronger than the usual one. Such scenario can be understood in terms of a phonon tunneling between inclusions, enhanced by the iso-orientation of all particles. Indeed, if a misorientation is introduced, the thermal conductivity strongly decreases. We also show that a percolating nanocomposite clearly stand in a different position than other nanocomopsites, where thermal transport is domimnated by the interface scattering, and where parameters such as the interface density play a major role, differently from our case.
Reference:
Enhanced thermal conductivity in percolating nanocomposites: a molecular dynamics investigation (Termentzidis, Konstantinos, Giordano, Valentina M., Katsikini, Maria, Paloura, Eleni, Pernot, Gilles, Verdier, Maxime, Lacroix, David, Karakostas, Ioannis and Kioseoglou, Joseph), In Nanoscale, The Royal Society of Chemistry, 2018.
Bibtex Entry:
@article{C8NR05734F,
 author = {Termentzidis, Konstantinos and Giordano, Valentina M. and Katsikini, Maria and Paloura, Eleni and Pernot, Gilles and Verdier, Maxime and Lacroix, David and Karakostas, Ioannis and Kioseoglou, Joseph},
 title = {Enhanced thermal conductivity in percolating nanocomposites: a molecular dynamics investigation},
 journal = {Nanoscale},
 year = {2018},
 bibyear = {2018},
 pages = {-},
 publisher = {The Royal Society of Chemistry},
 doi = {10.1039/C8NR05734F},
 url = {http://dx.doi.org/10.1039/C8NR05734F},
 abstract = {In this work we present a molecular dynamics investigation of thermal transport in a silica-gallium nitride nanocomposite. A surprising enhancement of the thermal conductivity for crystalline volume fractions larger than 5\% is found{,} which cannot be predicted by an effective medium approach{,} not even including percolation effects{,} the model systematically leading to an underestimation of the effective thermal conductivity. The behavior can instead be reproduced if an effective volume fraction twice larger than the real one is assumed{,} which translates in a percolation effect surprisingly stronger than the usual one. Such scenario can be understood in terms of a phonon tunneling between inclusions{,} enhanced by the iso-orientation of all particles. Indeed{,} if a misorientation is introduced{,} the thermal conductivity strongly decreases. We also show that a percolating nanocomposite clearly stand in a different position than other nanocomopsites{,} where thermal transport is domimnated by the interface scattering{,} and where parameters such as the interface density play a major role{,} differently from our case.},
}