Theoretical study of specific heat and thermal conductivity variation in nanomaterials
Komal Rawat and Monika Goyal
In the present paper, the authors study the specific heat dependence on shape, size and dimension of the nanomaterials. Using an analytic quantitative model for melting temperature, the expression of specific heat for nanomaterials is deduced. Further, the model is extended to study the shape, size and dimension effect on thermal conductivity of nanoparticles. Phonon scattering term is taken into consideration for calculation of thermal conductivity of nanomaterial to explain the roughness and scattering effect on thermal property. The specific heat is observed to increase from model calculations as size of the nanomaterial decreases. However, the thermal conductivity in nanoparticles is observed to decrease with size decrement of nanoparticle. It is observed that inclusion of phonon scattering term help to better understand the variation in thermal conductivity. The variation in specific heat and thermal conductivity with size is determined for spherical, regular tetrahedral, octahedral nanoparticles, cylindrical and hexagonal nanowires and nanofilms. The results calculated from model are in good consistency with the available experimental and simulated results and help to judge the suitability of the present model.
Keywords: specific heat; shape; size; dimension; thermal conductivity.