Molecular Dynamics Simulation Study on Thermal Transport in Graphyne/Polyaniline Composite System

Graphyne (GY) is a new carbon material with excellent electrical conductivity and low thermal conductivity (TC). The doping of GY into polymers to improve the thermoelectric properties of the material has become a hot research trend. In this study, molecular dynamics (MD) and nonequilibrium MD are used to study the effect of the number of oxidation units of polyaniline (PANI) on TC and heat transfer of PANI and GY/PANI systems. The geometric structure of polymer, interaction energy, and heat transport of all systems are studied and analyzed. It is found that (1) as the number of oxidation units of PANI increases, the interchain and intrachain heat transfers of PANI are decreased thereby decreasing the heat transfer of the PANI chains; (2) the weak interaction energy at the interface hinders the heat flux transfer, and the phonon vibration of GY and PANI mismatch at the interfaces; eventually the above reasons lead to low interface TC; (3) the doping of GY can effectively reduce the TC of the system. This study provides some research ideas and theoretical exploration for the application of polymer doped with GY composites in the field of thermoelectricity.