Effect of Elemental Doping on the Electrical and Thermal Properties of Porous BiFeO₃

Perovskite BiFeO 3 is a multifunctional oxide material with advantages such as low cost, high thermal stability, and low‐thermal conductivity. Currently, research on BiFeO 3 mainly focuses on its multiferroic and optoelectronic properties, whereas studies on its electrical and thermal properties are relatively rare. Herein, first‐principles calculations are employed to investigate the formation energies of 18 different dopants substituted at Bi sites in BiFeO 3 , including the isovalent anion Sb as well as cations with varying valence states. Bulk samples of pure porous BiFeO 3 and doped systems are prepared by solid‐state sintering, and electrical and thermal properties are characterized. Pure BiFeO 3 exhibited a low electrical conductivity of 7.78 Sm −1 at 300 °C. Doping BiFeO 3 with Yb effectively tunes its porosity, which in turn modulates its electrical conductivity. The Yb‐doped sample exhibits an electrical conductivity of 10.37 Sm −1 at 300 °C, representing an ≈33.3% increase compared to that of undoped BiFeO 3 . Although the thermal conductivity slightly rises from 0.96 to 1.26 Wm −1 K −1 at 300 °C, it remains relatively low compared to values reported in previous studies. This study provides new insights into the exploration of the electrical and thermal properties of BiFeO 3 materials.