Material-efficient preparation and thermoelectric properties of metallic NiₓAu₁₋ₓ films with large power factor

Abstract

Thermoelectric materials can utilize the Seebeck effect to convert electrical into thermal energy and vice versa. State-of-the-art research focuses on semiconductors as the band gap in their electronic density of states results in large values of the Seebeck coefficient. However, recent results suggest that certain metallic alloys such as NixAu1-x can also feature promising thermoelectric properties, relevant for technological applications [Sci. Adv. 9, eadj1611 (2023)2375-254810.1126/sciadv.adj1611]. In this work, we study the thermoelectric properties of NixAu1-x films on different substrates, with additional focus on a cost-efficient synthesis. Ultimately, a large power factor of 11.2mW/mK2 is achieved at 614K in Ni0.27Au0.73. Furthermore, by neglecting the phonon contribution to thermal conduction, which is negligibly small in these metallic systems well-obeying the Wiedemann-Franz law, a figure of merit of zT=0.15 is obtained at 763K.