Theoretical Prediction of the Monolayer Hf₂Br₄ as Promising Thermoelectric Material

The stability, electronic structure, electric transport, thermal transport and thermoelectric properties of the monolayer Hf₂Br₄ are predicted by using first principle calculations combined with Boltzmann transport theory. The dynamic stability of the monolayer Hf₂Br₄ is verified by phonon band dispersion, and the thermal stability is revealed by ab initio molecular dynamics simulations. The electronic structure calculation indicates that the monolayer Hf₂Br₄ is an indirect band gap semiconductor with a band gap of 1.31 eV. The lattice thermal conductivity of the monolayer Hf₂Br₄ is investigated and analyzed on phonon mode level. The calculation results of the electric transport explore the excellent electric transport properties of the monolayer Hf₂Br₄. The thermoelectric transport properties as a function of carrier concentration at three different temperatures are calculated. The study indicates that the monolayer Hf₂Br₄ can be an alternative, stable two-dimensional material with potential application in the thermoelectric field.