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Mesocrystalline Zn-Doped Fe3O4 Hollow Submicrospheres: Formation Mechanism and Enhanced Photo-Fenton Catalytic Performance

“…One is the replacement of the Fe 3+ ion with Zn 2+ in tetrahedral sites due to the Zn 2+ ion usually preferring tetrahedral sites. 42 Another is that the ion exchange based on the Kirkendall effect may favorably occur between the Zn 2+ ion and Fe 2+ ion in the Fe 3 O 4 mesocrystal, which could be attributed to similar ion radii of zinc ions in the tetrahedral environment and divalent iron ion radius in the octahedral environment [(rZn 2+ ) tetra = 0.60 nm and (rFe 2+ ) octa = 0.61 nm]. 41 Doping effect was further confirmed by EDX mapping images.…”

Tailoring of structural, electrical and magnetic properties of BaCo2 W-type hexaferrites by doping with Zr–Mn binary mixtures for useful applications

“…However, relaxation peak intensity decreases with increase in the dopant concentration level because the substitution of impurity atoms reduces the number of iron ions in the sample. Furthermore, the substitution of diamagnetic ions has been reported [34] to reduce tan d; in this case, zirconium is a diamagnetic ion. As both electrical conductivity and dielectric behavior are transport properties whose variations are proportional to the sample composition, similar mechanism may be responsible for these two phenomena.…”

Pyroelectric Response and Conduction Mechanism in Highly Crystallized Ferroelectric Sr3(VO4)2 Ceramic

“…The lower value of activation energy (E a ) in the low-temperature region suggests the presence of a hopping-type conduction mechanism in the material due to singly ionized oxygen vacancies and small polarons. 46,47 Secondly, it is well known that motion of oxygen vacancies gives rise to an activation energy of about 1 eV. From these activation energy values, it is clear that the conduction in the high-temperature range occurs due to ionic charge carriers or oxygen ion vacancies.…”