Fig. 5.

Thermolectric performance of MoS₂/h-BN heterostructure. (A) Seebeck coefficient and mobility as function of temperature at V_g = 70 V for MoS₂/h-BN device. (B) Total S values of MoS₂/h-BN sample at n = 2 × 10¹² cm⁻² are contributions from the energy-dependent diffusive part $S_{\mathrm{N}}$, phonon-drag part S_ph, and the Kondo scattering part $S_{\tau }$. At a fixed n, the total S first exhibits a diffusive negative value at high temperatures from conducting electrons described by $S_{\text{N}}+S_{ph}$. As the temperature decreases, the conventional diffusive contribution is weakened, and the Kondo scattering term $S_{\text{τ}}$ starts to dominate and shows large positive values. As temperature is decreased further, all of the physical interactions start to freeze, and the total S goes back to zero as expected (64). (C) Comparison of PF of MoS₂/h-BN and MoS₂/SiO₂ sample as a function of temperature at different gate voltages. Additional band hybridization-induced peaks as high as 50 mW m⁻¹ K⁻² can be observed at 30 K ∼ 50 K for MoS₂/h-BN sample. (D) The PF value of our MoS₂/h-BN heterostructure shows superior thermoelectric performance compared to even the highest reported values in other 2D materials at room temperature. [G/SiO₂ and h-BN (50), MoS₂ (36, 37), WSe₂ (60), TiS₂ (61, 62), and BP (51).]