Theoretical Study of Magnetization and Electrical Conductivity of Ion‐Doped KBiFe2O5 Nanoparticles

The electrical conductivity σ and magnetization M of (KBFO) nanoparticles (NPs) are systematically examined using a microscopic model and Green's function theory. KBFO is characterized by a narrow bandgap and relatively weak electrical conductivity σ, which presents a problem in carrier transportation and collection. Therefore, ways to enhance σ are found. The first is reducing the NP size. The second one is doping at the Fe and Bi sites with different ions which cause a compressive strain, that is, their ionic radius is smaller than that of the host ion. It is shown that doping with Al at the Fe site as well as with Ru or La ions at the Bi site leads to enhancing the electrical conductivity σ. The magnetization M increases with increasing concentration of all dopants.