XO2 (X = Pd, Pt) Monolayers: A Promising Thermoelectric Materials

Abstract

AbstractIn this work, the structural, thermoelectric, and electronic properties of XO2 (X = Pd, Pt) monolayers are investigated using density functional approach and Boltzmann transport equations (BTE). These materials are semiconductor in nature having indirect band gap 1.40 (1.69 eV) for PdO2 (PtO2) monolayers. These materials are chemically as well as dynamical stable. The observation of a sharp peak in the vicinity of the Fermi level indicates a high value of the Seebeck coefficient (S). The calculated value of S is 2269 (2734) µV K−1 with respect to n (p)‐type doping at carrier concentration of 1.12 (2.33) × 1013 cm−2 for PdO2 (PtO2) monolayer at 300 K. Calculations reveal a lattice thermal conductivity (κl) of 15.85 and 12.41 Wm−1K−1 for PdO2 and PtO2 monolayers, respectively at room temperature. Monolayer PtO2 shows a larger S and smaller k as compared to PdO2. Due to the maximum value of power factor and minimum value of lattice thermal conductivity, ZT for n‐type doped PtO2 monolayer (1.04) is higher than PdO2 monolayers (0.87). The findings provide a blueprint for evaluating the thermal energy conversion efficiency of XO2 monolayers for potential thermoelectric applications.