Influence of nanoparticle size distribution on the thermal conductivity of particulate nanocomposites

Conventional models for the thermal conductivity of nanocomposites neglect the particle size distribution by assuming all nanoparticles to be uniform in size, although in reality most particles in a nanocomposite are not uniform and the size distribution of the nanoparticles might strongly affect the thermal conductivity of nanocomposites as demonstrated in this letter. By including the lognormal distribution of the nanoparticle size into the thermal conductivity model of nanocomposites embedded with spherical particles, we show that the mean value and the standard deviation (SD) of the nanoparticle radius significantly affect the thermal conductivity of particulate nanocomposites. At the same mean radius of embedded particles, the thermal conductivity of the nanocomposite with lognormal size distribution at SD = 56 can be twice that with a uniform particle size. Our improved model on effective thermal conductivity of nanocomposites with nonuniform particles can provide a more accurate prediction on the thermal conductivity of realistic particulate nanocomposites. Copyright (C) EPLA, 2017