Abstract
Thermoelectric (TE) materials offer a promising pathway toward achieving carbon neutrality by converting waste heat into electricity. The enhancement of their figure-of-merit (zT) depends on optimizing the composition of materials and nanostructures, reducing the thermal conductivity, and increasing the power factor. Cu(2)Se, a superionic material, achieves a zT of 0.4 at 300 K by facilitating Cu ion movement within its face-centered cubic lattice, effectively suppressing thermal conductivity. Herein, we present a novel TE material developed by doping Cu(x)Se crystals of different compositions with FeSi(2). We report a remarkable zT of 0.69 at 298 K for Cu(2)Se-based materials and reveal the presence of the CuO and Cu(2)O tiny crystals on the material surface, uniform dispersion of Si within the film, and formation of distinctive amorphous FeO. Our strategy holds great potential for notably advancing waste heat recovery in sustainable TE materials.