Reasons for the High Electrical Conductivity of Bismuth Ferrite and Ways to Minimize It

Abstract

The reasons for the high electrical conductivity of bismuth ferrite due to its natural composite structure, structural non-stoichiometry, redox processes, and the boundary position in the perovskite family have been considered. It has been shown that it is possible to significantly (2–3 orders of magnitude) reduce the conductivity of BiFeO3 by introducing large-sized ions of rare-earth elements (REE: La, Pr, Nd, Sm, Eu, Gd with 0.94 ≤ R¯ ≤ 1.04 Å) in amounts of up to 10 mol %. An interpretation of the observed effects has been given. A consideration about the appropriateness of taking into account the presented results when developing devices using materials of the BiFeO3/REE type has been expressed.

Composition-, temperature- and pressure-induced transitions between high-pressure stabilized perovskite phases of the (1-x)BiFe0.5Sc0.5O3 - xLaFe0.5Sc0.5O3 series

“…In addition to the evident possibilities of practical applications of BiFeO 3 as multiferroic material in magnetic field sensors, electrically switchable magnets, magnetic memory and spin electronic devices [2], new areas of applications such as photovoltaics, photocatalysis, and electric energy storage [3][4][5] were recently demonstrated. However, in the overwhelming majority of cases, practical application of BiFeO 3 requires chemical modifications, which are generally needed to overcome the drawbacks intrinsic to this compound, namely high values of both the N eel temperature and the Curie point, the modulated spin ordering that averages the net magnetization to zero and very high electroconductivity [1,6,7].…”