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Page 10 of 14 Kautsar et al. Energy Mater. 2025, 5, 500129 https://dx.doi.org/10.20517/energymater.2025.26

Figure 6. (A) A and ϕ images at J = 1.0 A, and f = 1 Hz for HP, HD, and RE-Cu (RE = Dy-Nd, Nd, Pr) GBDP HD magnets; (B)
odd odd c
Frequency dependence of the A /j (C) ϕ (D) Π and S , (E) z T for same studied magnets. HP: Hot-pressed; HD:
odd c odd AEE ANE ANE
hot-deformed; GBDP: grain boundary diffusion process; S ANE : anomalous nernst coefficient; AEE: anomalous Ettingshausen effect.
IGP into a crystalline phase after GBDP. This reduction leads to an increase in the total S . The α , which
xy
ANE
is often used to evaluate the thermoelectric performance of ANE, is shown in Figure 7D. It can be seen that
the absolute value of α only experiences a slight increase after HD and a slight decrease after GBDP,
xy
indicating that it remains relatively unchanged throughout these processes.
Finally, we discuss potential strategies to further enhance the S and z T of Nd-Fe-B permanent
ANE
ANE
[27]
magnets. Based on this study and previous work on commercial sintered magnets , we observe that the
contributions from S and S in Nd-Fe-B magnets tend to have opposite signs, leading to a small S due to
I
ANE
II
the destructive summation of the two components. The formation of crystalline IGP in Nd-Fe-B magnets
could potentially increase S by reducing the S magnitude or changing its sign. However, this increase in
ANE
II
S is somewhat offset by the rise in κ resulting in a smaller enhancement of z T. To further enhance both
ANE
ANE
S and z T in Nd-Fe-B magnets, it is also necessary to increase the S component, without significantly
ANE
ANE
I
increasing κ. This can be achieved by enhancing α , which is fundamentally tied to the Berry curvature at
xy
the Fermi level [59,60] . Tuning the Berry curvature near the Fermi level or equivalently, tuning the Fermi level
position, has been shown to effectively enhance the transverse thermoelectric coefficient α , as
xy