Activation of oxide-ion conduction in KNbO3 by addition of Mg2+

作者:Li LP; Li GS*; Smith RL; Inomata H
来源:Applied Physics Letters, 2002, 81(15): 2899-2901.
DOI:10.1063/1.1512957

摘要

Niobate perovskite oxides of KNb1-xMgxO3-delta were synthesized directly at high temperature and pressure. X-ray diffraction confirmed the formation of single-phase orthorhombic structures. High-temperature Raman spectroscopy in combination with thermal analysis showed that phase transitions occurred from orthorhombic to tetragonal, to pseudo cubic, and finally to cubic, in sequence. Addition of Mg2+ at the Nb5+ sites of perovskite KNbO3 lattice led to a dramatic enhancement of oxide-ion conduction. This enhancement in oxide-ion conduction was through the suppression of the contribution from p-type holes, which shows that these high-temperature phases can be promising candidates as conductive materials.