Molecular Simulation Study on Electronic Property and Thermal Conductivity of Graphyne/Polypyrrole Composite

Graphyne is a new carbon material with excellent electrical conductivity. It is a research hotspot that using graphyne as polymer filler to enhance the thermal conductivity of composite materials. In this study, the structure, electronic properties, and thermal conductivity of graphyne (GY), polypyrrole (PPy), and graphyne/polypyrrole (GY/PPy) composite materials are studied using density functional theory (DFT), molecular dynamics simulation (MD), and nonequilibrium molecular dynamics simulation (NEMD). It is found that graphyne with approximate aspect ratio has better electronic conductivity. The thermal conductivity of GY/PPy composites with different mass fractions is studied by NEMD. The results show that when 7-GY-2 is 20%, the thermal conductivity of GY/PPy composite is about 90% higher than that of pure PPy. In order to further study the interaction of GY/PPy, the electronic properties of the local configuration (GY-PPy) of the composite are studied. The results show that the strong interaction between graphyne and polypyrrole improves the conductivity of GY-PPy. This study provides some research ideas and theoretical exploration for improving the electrical conductivity and thermal conductivity of polymer doped with graphyne.