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

Abstract

In 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.

Equibiaxial strain regulates the electronic structure and mechanical, piezoelectric, and thermal transport properties of the 2H-phase monolayers CrX2 (X = S, Se, Te)

“…Considering the vacuum space of the 2D material, the lattice thermal conductivity k l of the 2D material can be obtained by multiplying the lattice thermal conductivity of the three-dimensional material by a reduction factor. The formula is as follows 78–80 . Overall, the lattice thermal conductivity obeys the trend CrS 2 > CrSe 2 > CrTe 2 .…”

The thermoelectric properties of CdBr, CdI, and Janus Cd2BrI monolayers with low lattice thermal conductivity

“…At 600 K, the maximum zT values are 1.54, 3.03, and 1.71 for the p-type doping CdBr, Cd 2 BrI and CdI monolayers, respectively. Particularly, the zT value of p-type doped Janus Cd 2 BrI at 600K is higher than that of PtO 2 ( zT = 1.04 at 700 K) 67 and SnSe 2 ( zT = 1.1 at 900 K), 68 making it a promising material for application in medium temperature TE devices such as thermal insulators and low power thermoelectric refrigerators.…”

Realizing new 2D spintronic materials from the non-magnetic 1T-PdO2 monolayer through vacancy defects and doping

“…There are very few works reporting about this 2D material. Recently, Wani et al 46 have predicted promising thermoelectric performance for the PdO 2 monolayer. Results indicate its semiconductor nature with a band gap of 1.40 eV.…”