Influence of different nanoparticles embedded in crystalline carbon monoxide matrix on heat transfer in the nanocomposite

Abstract

The preliminary results of investigations of heat transfer in nanocomposites consisting of nanoparticles randomly distributed in solid carbon monoxide matrix are presented. In the experiment the thermal conductivity coefficient dependence on temperature for CO crystal with silica and palladium nanoparticles of different size embedded in the crystal structure was determined over the temperature range 2.2-35 K by steady-state heat flow method. The results of the measurements were analyzed within the frame of relaxation time approximation. The analysis shows that lowering of the thermal conductivity of the nanocomposites relative to pure carbon monoxide crystal observed for both types of the investigated nanoparticles, palladium and silica, is caused mostly by scattering of phonons by boundaries of the nanoparticles. Additionally, the presence of the nanoinclusions promotes higher density of dislocations and influences the matrix lattice dynamics.