Thermal Energy Transport in Graphene/Graphitic Carbon Nitride Film

Recently, graphene/graphitic carbon nitride films have been successfully fabricated, in which graphitic carbon nitride (GCN) acts as a linker to covalently bind graphene (GE) sheets. In this investigation, the regulation mechanism of the interfacial thermal conductance (ITC) and thermal conductivity (TC) in the in-plane and out-of-plane directions in the GE/GCN composite film is explored based on internal structural alterations (size and defects) and external influence factors (temperature and strain) using molecular dynamics simulations. In the out-of-plane thermal transport, the ITC of the van der Waals weak coupling interface increases significantly when the number of GE layers, defect concentration, temperature, and compressive strain rise, but it remains unchanged as the number of GCN layers increases. The TC rises with the increase in the number of GE and GCN layers, defect concentration, temperature, and compressive strain. In the in-plane thermal transport, the ITC of the covalent strong coupling interface increases with increasing GE size, defect concentration, and temperature, while reducing with increasing GCN size and remaining constant with increasing compressive strain. The TC increases as GE and GCN sizes become longer, reduces when defect concentration and temperature increase, and does not change as compressive strain rises. The findings provide a comprehensive understanding of the internal thermal transport mechanism of the GE/GCN film.