Fig. 4.

Thermoelectric transport and Seebeck coefficient measurement of defective MoS₂ on h-BN substrate. (A) Comparison of S vs. T of MoS₂/SiO₂ and MoS₂/h-BN device at V_g = 70 V (circle), 50 V(square), and 30 V (diamond) (from left to right; black arrow). The solid lines guide the eye. MoS₂/SiO₂ sample shows negative values due to the diffusive type n-type charge carriers. For MoS₂/h-BN sample, at low temperatures, an anomalous sign change in S occurs where the majority carriers are electrons. (B) Color contour plot of S values versus V_g and T for MoS₂/h-BN device. The black dotted line indicates the point with S ∼ 0 mV/K. (C) Total S values of MoS₂/SiO₂ sample at n = 2 × 10¹² cm⁻² and its respective contributions from the energy-dependent diffusion $S_{\mathrm{N}}$ and phonon-drag S_ph.