Scattering-tuned metal thermoelectrics, a new paradigm

In contrast to conventional semiconductor materials, this review outlines a new strategy for metals to be high-performance thermoelectric materials. We have proposed “intrinsic energy filtering” as a strategy to overcome the inherently low Seebeck coefficients in metals. This strategy involves engineering electronic structures where a dispersive conduction band and a localized flat band coexist near the Fermi level, creating strong energy dependence in the carrier relaxation time, thereby generating a large Seebeck coefficient S . Effectiveness has manifested in distinct material systems; Ni–Au alloys, where disorder-mediated s – d interband scattering achieves exceptionally high power factors ∼34 mW m −1 K −2 . Ni 3 Ge exhibits a relatively large S ∼−80 μV K −1 through interband scattering. The strategy was further extended to the Kagome metal Ni 3 In, with topological flat bands, revealing that Zener tunneling can suppress S, and we outline strategies to circumvent this quantum transport phenomenon. These developments point to a new horizon for the development of next-generation thermoelectric materials, unlocked by the precise control of scattering mechanisms.