Achieving High Thermoelectric Performance of SnTe Composites with 2D WSe2

In this work, we introduced two-dimensional (2D) WSe 2 with the lowest heat conductivity to enhance thermoelectric properties of the non-toxic and cost-effective SnTe. On one hand, the improved power factor can be attributed to the enhancement of Seebeck coefficient due to the decrease of low-energy carriers and minority carriers by the addition of WSe 2 -SnTe p - p -type heterojunction interface barriers. On the other hand, the thermal conductivity also decreased sharply by the heightened phonon scattering from the high-density stacking faults and multiscale hierarchical architectures. Ultimately, benefiting from the dual regulation effect of the introduction of 2D WSe 2 on the electro-acoustic decoupling, an improved figure of merit ( ZT ) of 1.0 is achieved for the composition of SnTe + 6 wt% WSe 2 at 873 K, which is enhanced by 134% in comparison with the pure SnTe sample. Moreover, the meaningful attempt represents an effective and feasible strategy for mixing SnTe with other compounds by the method of ball milling. Graphical Abstract