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Page 14 of 21 Duparchy et al. Energy Mater. 2025, 5, 500134 https://dx.doi.org/10.20517/energymater.2025.51

Table 3. Nominal composition, sample labelling, room temperature charge carrier concentration n , Hall mobility μ at room
H
H
temperature and density of states effective mass of Mg 1.95 Si 0.233 Sn Sb 0.06 -II and Mg-rich doped samples before and after Mg
0.7
loss from Sankhla et al. [57]
2
Nominal composition Sample labelling n × 10 (cm ) μ (cm /Vs) (m )
-3
20
H
H
0
Mg 1.95 Si 0.233 Sn Sb 0.067 Sample 1 [Mg-poor] 2.5 52.3 2.1
0.7
Mg 2.06 Si 0.385 Sn Sb 0.015 Sample 2 [Mg-rich] 2.0 49.2 2.4
0.6
before Mg loss
Mg 2.06 Si 0.385 Sn Sb 0.015 Sample 2 [after Mg loss] 1.5 41.0 2.4
0.6
after intermediate Mg loss
Mg 2.06 Si 0.385 Sn Sb 0.015 Sample 2 [Mg-depleted] 0.3 - 1.8
0.6
after Mg loss - fully Mg depleted

Figure 5. (A) Density of states effective mass as a function of temperature for the Mg Si Sn Sb -II sample. The effective
1.95 0.233 0.7 0.067
mass was obtained from room temperature Hall measurement, assuming a constant carrier concentration; (B) Weighted mobility (μ )
w
and Hall mobility (μ ) of Mg 2.06 Si 0.385 Sn Sb 0.015 and Mg 1.95 Si 0.233 Sn Sb 0.067 -II.
0.7
H
0.6
m = ( ), with N = 6.
s
V
The alloy scattering mobility ( ) is given by:

(10)

with N being the number of atoms per unit volume, x being the Sn + Sb fraction at the X site and E the
AS
0
alloy scattering potential.
Last but not least, the mobility constant of grain boundary scattering ( ) is defined by:

(11)

where B is the grain size, which is kept constant (B = 5 µm) and E is the potential barrier at the grain
[57]
B
boundary (called barrier height).