Graphene-carbon nitride interface-geometry effects on thermal rectification: a molecular dynamics simulation

We apply the non-equilibrium molecular dynamics approach (NEMD) to study thermal rectification in a hybrid graphene-carbon nitride system (G - C3N) under a series of positive and negative temperature gradients with varying interface geometries. In this study, we investigate the effects of a) temperature differences, (∆T), between the two employed baths, b) mediainterface geometry, and c) sample size, on thermal rectification. Our simulation results portray a sigmoid relation between thermal rectification and temperature difference, with a sample-size depending upper asymptote occurring at generally large temperature differences. The achieved thermal rectification values are significant and go up to around 120% for ∆T = 150 K. Furthermore, the consideration of varying media-interface geometries yields a non-negligible effect on thermal rectification and highlights areas for further investigation. Finally, calculations of Kapitza resistance at the G - C3N interface are performed for assisting us in the understanding of interface-geometry effects on thermal rectification.