Thermoelectric properties of 2D semiconducting Pt2CO2

Abstract

Quantum confinement effect in 2D materials leads to the reduction of the degree of freedom of space and the weakening of the correlation between the thermoelectric factors. Only by adjusting a certain physical quantity can optimized the thermoelectric performance. MXenes as a new class of 2D material have attracted widely attention due to their good mechanical and chemical stability, controllable layer thickness, easily functionalized surface and excellent electrical conductivity. In the present paper, using first-principles calculations, we design and study the stability, electronic and thermoelectric properties of 2D monolayer Pt2CO2. Results show that the Pt2CO2 is a new non-magnetic semiconductor, and can bear its own weight, and maintain its free-standing planar structure without substrate support. Futher, the stable calculations indicate that the Pt2CO2 meets thermodynamic, mechanical and dynamic stabilities. Finally, using the Boltzmann transport theory combined with Slack model, we calculate the Seebeck coefficient S, electrical conductivity σ/τ, and the thermal conductivity κ, and then obtain the ZT value from 300 K to 1000 K. It is found that the largest ZT value closes to 1.05 at 1000 K, implying the Pt2CO2 potential application as thermoelectric material.