Thermal Transport Properties Of ?-antimonene:First-principles Study

The direct transformation between heat energy and electric energy can be realized through the simple physical principle of thermoelectric effect,and this direct transformation for the waste heat power generation and thermoelectric cooling or heating provides a simple and effective way.Thermoelectric materials is the choice to realize the transformation,and also a development prospect of fairly good green energy materials.Based on density functional theory of first principles combined with the semiclassical Boltzmann transport equation,we investigated the thermal transport properties of ?-antimonene.We first calculated the Seebeck coefficient under different temperature,electrical conductivity,electronic thermal conductivity with various chemical potential,electron and hole doping concentration;Secondly we gives the phonon dispersion,phonon group velocity and the phonon relaxation time with the change of frequency and the lattice thermal conductivity under different temperature,and we also calculated each phonon contribution to the whole lattice thermal conductivity.Finally,we compared the ?-antimonene under different temperature with the various chemical potential,electron doping concentration,hole doping concentration of three cases of thermoelectric optimal value.The results show that the ?-antimonene is a stable two-dimensional structure;three acoustic phonons near ? are almost linear;acoustic phonons accounts for 96.68%of the lattice thermal conductivity,optical phonons accounts for only 3.32%of the lattice thermal conductivity;each phonon group velocity shows very weak of anisotropicity,and because of ZA phonon at ? point is linear and thus there exists nonzero group velocity.As shown in our results for the ?-antimonene,by changing the chemical potential to improve the thermoelectric performance of materials is feasible,and the ZT value maximum is 0.275 near the Fermi surface.To improve the thermoelectric performance by changing the carrier concentration,we find that electron doping is better than hole doping which the ZT value can reach 0.215 by electron doping while it as low as only 0.06 via hole doping.