Low loss giant dielectric and electrical transport behavior of KxTiyNi1−x−yO system

Abstract
The K x Ti y Ni 1 − x − y O system in the series A x Ti y Ni 1 − x − y O ( A = Li , K, Na; x = 0.05 – 0.30 , y = 0.02 ) shows the highest dielectric constant ε ′ ∼ 10 5 and lowest loss. The high ε ′ value is attributed to microstructures, which form boundary layer capacitors. Electrical conductivity in these materials follows small polaron hopping mechanism in the nonadiabatic regime. Unlike Li x Ti y Ni 1 − x − y O and Na x Ti y Ni 1 − x − y O (NTNO), K x Ti y Ni 1 − x − y O (KTNO) exhibits an anomaly around T p ∼ 430 K . T p shifts to the lower temperature range with increasing K content which is related to the higher ionic radius of K.