Enhancing Thermoelectric\nEfficiency in Twisted Bilayer\nPdSe<sub>2</sub>

PdSe<sub>2</sub> is a promising two-dimensional (2D)\nmaterial that\nhas garnered significant attention for thermoelectric energy conversion\napplications due to its exceptional electronic and thermal properties.\nThis study investigates the effect of twisting on the electron and\nphonon transport, as well as the thermoelectric properties of monolayer–twisted\nbilayer–monolayer PdSe<sub>2</sub> devices using full self-consistent <i>ab initio</i> nonequilibrium Green’s function methods\ncombined with density functional theory. Our findings reveal that\n90° twist angle significantly enhances the figure of merit (<i>ZT</i>), achieving values of 3.95 at 300 K and 6.25 at 600 K,\nan 81.19% increase at room temperature compared to nontwisted configurations.\nThis enhancement is primarily due to the tunability of the band gap,\nweakened interlayer coupling, and boundary scattering at the interface.\nAdditionally, our analysis suggests that adjusting the interlayer\ncontact length could further optimize <i>ZT</i>. Achieving <i>ZT</i> values exceeding 3 in twisted bilayer PdSe<sub>2</sub> emphasizes the potential of exploiting twist modulations in 2D materials,\nrepresenting significant progress toward developing highly efficient\nnanodevices capable of converting waste heat into electrical energy.