where 𝑘 𝐵 is the Boltzmann constant, e represents the elementary charge, h denotes Plank's constant, n is the carrier concentration, and 𝑚 𝐷𝑂𝑆 * represents the DOS effective mass. Thus as witnessed in Figures and, the Seebeck coefficient typically exhibits opposite dependence on temperature and carrier concentration compared to the electrical conductivity, decreasing with carrier concentration and increasing with temperature due to their effects on carrier diffusion (and corresponding voltage) across a temperature gradient in a material. For both n and p-type conditions, we see that the Seebeck coefficient in Sc2Si2Te6 consistently exceeds that of Sb2Si2Te6, showing the opposite behaviour to the electrical conductivity. In particular, n-type Sc2Si2Te6 retains a large Seebeck coefficient (S > 300 μV/K) even at relatively high carrier concentrations (n = 10 20 cm -3 ) and electrical conductivities (σ ~ 10 5 S/m). According to equation 1, for a given carrier concentration and temperature, the Seebeck coefficient is primarily determined by the DOS effective mass -which can be approximated by the equation 𝑚 𝐷𝑂𝑆 * = 𝑁 𝑣 2 3 𝑚 * . Here, Nv is the number of valleys in the electronic band structure and m * is the effective mass within a single valley. As discussed previously, Sc2Si2Te6 exhibits increased band degeneracy (18 and 2 for n and p-type, respectively, vs 1 for both carrier types in Sb2Si2Te6) and carrier effective masses (Table ) compared to Sb2Si2Te6, elucidating the origins of increased Seebeck coefficients for Sc2Si2Te6.