Electrical Conductivity in Fe 1‐x O‐MgO Solid Solutions

Solid solutions of magnesium oxide containing iron oxide in concentrations varying from a few percent to 100% were fabricated in polycrystalline form for studying the mechanism of electrical conduction. These semiconductors were ohmic in the range 0 to 10 v/cm, conducted by hole transfer, and showed reproducible conductivity data from room temperature to about 300°C. The conductivity of these solid solutions increases with increasing Fe 3+ concentration. The electrical conductivity is also dependent on the total iron oxide content, decreasing rapidly (nonlinear dependence) as Fe 1‐ x O is diluted with MgO. The activation energy for electrical conduction varies from 0.1 to about 0.5 ev for the dilute solid solutions (less than about 15 cation % iron).