Structural and dielectric properties of yttrium substituted nickel ferrites.

Highlights: [•] Dense NiFe2−x Y x O4 ceramics (with 0≤ x ≤0.3) were prepared. [•] Pure spinels were obtained for x ≤0.07 while for x ≥0.15 samples had secondary phases. [•] With addition of yttrium, ac conductivity slightly increased. [•] We suggest several effects that can explain the observed changes in ac conduction. [•] With addition of yttrium, dielectric constant increased while the tg δ decreased. [ABSTRACT FROM AUTHOR]