In-Plane Seebeck Coefficients of Thickness-Modulated 2D PtSe2Thin Films

Abstract

Two-dimensional (2D) PtSe2 is rapidly emerging as a promising candidate for developing devices that exhibit a significantly enhanced thermoelectric power factor because of its thickness-modulation-induced tunable semiconductor-to-semimetal transition characteristic. This interesting phenomenon motivated us to measure the in-plane Seebeck coefficients and electrical conductivities of large-area 2D PtSe2 thin films with approximately 2-15 nm thicknesses. We observed an outstanding in-plane Seebeck coefficient of ∼73.7 μV/K and a high electrical conductivity of ∼216 S/cm in the 9-nm-thick 2D PtSe2 film than in the ∼6-nm-thick 2D PtSe2 film at 300 K. Our observations suggest that thickness-dependent semiconductor-to-semimetal transitions in PtSe2-based materials offer a distinguishable advantage for enhancing the power factor of 2D PtSe2-based thermoelectric devices. ©