Supplement Number1

The Supplemental Material for computational details, validation of electronic and phononic band structures of t-TaN, crystal structure and bonding strength analysis of TaX (X=As, P, N); thermodynamic stability, convergence tests for thermal conductivity and carrier mobility of t-TaN, electronic thermal conductivity, temperature-induced phonon renormalization, normal and umklapp scattering processes of t-TaN, and the comparison of phonon transport properties of θ-TaN and t-TaN.