The effect of finite-temperature and anharmonic lattice dynamics on the thermal conductivity of ZrS₂ monolayer: self-consistent phonon calculations

Two-dimensional (2D) ZrS2 monolayer (ML) has emerged as a promising candidate for thermoelectric (TE) device applications due to its high TE figure of merit, which is mainly contributed by inherently low lattice thermal conductivity. This work investigates the effect anharmonicity driven temperature-dependent phonon dispersions on transport ML. The calculations are based self-consistent (SCP) theory calculate thermodynamic parameters along with higher- order (quartic) force constants were extracted using an efficient compressive sensing dynamics technique, estimates necessary data emerging machine learning program alternative computationally expensive density functional calculations. Resolve degeneracy and hardening vibrational frequencies low-energy optical modes predicted upon including quartic anharmonicity. As compared conventional Boltzmann equation (BTE) approach, conductivity optimized ML unit cell within SCP + BTE approach found be significantly enhanced (e.g., 21% at 300 K). enhancement relatively lower value linewidth anharmonic frequency renormalization included in theory. Mainly, neglects temperature dependence consideration harmonic treats normal process three-phonon scattering incorrectly use quasi-particle lifetimes. These limitations addressed this signifies validity accuracy approach.