Tunable thermoelectric properties of SnS2 under high pressure at room temperature

In this paper, we study the structural, electronic, vibrational, thermoelectric and elastic properties of tin disulfide (SnS2) using first principles density functional theory calculations in the pressure range 0 ≤ p ≤ 5 GPa. The variation of lattice constant along c-axis is found to be higher than that along the a-axis which significantly affects the properties. The electronic band gap is observed to decrease with the applied pressure. The Raman shift of Eg and A1g modes increases with applied pressure. Furthermore, SnS2 remains dynamically stable up to 5 GPa. Thermoelectric properties such as thermopower (S), electrical conductivity (σ), power factor (S2σ) show anisotropy. While the in-plane direction is more dominant at ambient pressure, the out-of-plane is more dominant with the increase in pressure. The calculated power factor is higher in the hole concentration than the electron concentration in the defined pressure range at room temperature. This suggests that SnS2 could be an excellent candidate material of p-type thermoelectric under high pressure conditions. •The strong pressure dependence for power factor in p-type doping shows that the SnS2 under pressure may become a more efficient thermoelectric material.•The thermal conductivity of SnS2 is estimated from elastic constants and which is found to be increasing with pressure.•Computed phonon frequencies and phonon dispersion curves have been reported at various pressures (p ≤ 5 GPa).