Investigation of thermal property of triangle vacancy nitrogen-doping graphene nanoribbons

Abstract

ABSTRACTUnder different ratios of nitrogen atoms at 200 ~ 600K temperature range, we study thermal conductivity and heat rectification of NTGNs (Nitrogen-doping beside Triangle vacancy Graphene Nanoribbons) by using reverse non-equilibrium molecular dynamics simulation. The graphene nanoribbons are armchair graphene nanoribbons (AGNRs), and the length and width are 19.3nm and 3.7nm respectively. We find that thermal conductivity increases more than 30 when nitrogen atoms first replace 12 carbon atoms beside vacancy defect. Then as the proportion of nitrogen atoms increases from 0.85% to 7.2%, the thermal conductivity gradually decreases. Besides, the thermal conductivity of NTGNs becomes more and more insensitive to temperature with the increase of concentration of nitrogen atoms. In addition, we find that heat flow from left (L) to right (R) flows easily and the thermal rectification has a rising trend with the increase in the scale of nitrogen atoms at different temperatures. Moreover, phonon power spectra of the atoms are calculated to explain thermal rectification phenomenon. These findings will make a greater contribution to the design of heat transfer controlling and thermal rectifier.