AgSe Nanorod Arrays with Ultrahigh Room Temperature Thermoelectric Performance and Superior Mechanical Properties.

AgSe is an intriguing material for room-temperature energy harvesting. Herein, we report the fabrication of AgSe nanorod arrays by glancing angle deposition technique (GLAD) followed by simple selenization in a two-zone furnace. AgSe planar films of different thickness were also prepared. The unique tilted AgSe nanorod arrays show excellent = 1.14 ± 0.09 and a power factor of 3229.21 ± 149.01 μW/m-K, respectively, at 300 K. The superior thermoelectric performance of AgSe nanorod arrays compared to planar AgSe films could be ascribed to the unique nanocolumnar architecture that not only facilitates efficient electron transport but also significantly scatters phonons at the interfaces. Furthermore, the nanoindentation measurements were performed to explore mechanical properties of the as-prepared films. The AgSe nanorod arrays showed hardness values of 116.51 ± 4.25 MPa and elastic modulus of 10,966.01 ± 529.61 MPa, which are lowered by 51.8 and 45.6%, compared to AgSe films, respectively. The synergetic dependence between the tilt structure and thermoelectric properties accompanied with the simultaneous improvement in mechanical properties opens a new avenue for the practical applications of AgSe in next-generation flexible thermoelectric devices.