Hydrogenation and oxidation enhances the thermoelectric performance of Si2BN monolayer

Abstract

In the present study, we have investigated the structural, electronic, and charge transport properties of pristine, hydrogenated, and oxidized Si₂BN monolayers via first-principles calculations based on density functional theory (DFT). Hydrogenation and oxidation of Si₂BN monolayer display negative binding energy therefore these structures are energetically favorable. The electronic band structure engineered by the hydrogenation and oxidation of the Si₂BN monolayer transformed from metallic to semiconducting nature. Due to the hydrogenation and oxidation of Si₂BN, the monolayer also changes from a planar structure to a non-planar structure. The hydrogenated and oxidized structures led to high thermoelectric performance as compared to the pristine Si₂BN monolayer. When the Si₂BN monolayer is hydrogenated and oxidized, its electronic figure of merit (ZT_e) significantly enhanced from 0.45 to 0.99. The investigation results suggest a practical approach for improving the performance of thermoelectric properties of the Si₂BN monolayer.