Preparation and electrical properties of KCa2–xLaxNb3O10

Abstract

Electron-doped layered perovskite KCa_2–xLa_xNb₃O₁₀ was prepared from KNbO₃, Nb₂O₅, Nb, La₂O₃ and KCa₂Nb₃O₁₀ at 1200°C for 10 h under Ar. Essentially single-phase KCa_2–xLa_xNb₃O₁₀ with plate-like morphology was obtained with 0⩽x⩽ 0.3, and lattice parameters increased with increasing x. All the La-doped products showed semiconducting behaviour. Linear (log ρ)–T relationships were clearly observed, but the resistivity behaviour deviates from the linear relationship at lower temperatures. A possible conduction mechanism is discussed.