Temperature dependent resistivity changes of YTaO4-based ceramics

Here, systematic investigation was conducted on the negative temperature coefficient (NTC) behaviors of YTaO 4 -based ceramics (YTaO 4 , Y 1/2 Ce 1/2 TaO 4 and Y 1/3 Ce 1/3 Pr 1/3 TaO 4 ) characterized by a metastable monoclinic M-phase (I2/a) and prepared via conventional sintering. For YTaO 4 -based ceramics, the addition of 1% Al 2 O 3 sintering aid not only promotes densification and improves sintering performance, but the formed intergranular phase also effectively inhibits secondary recrystallization of the ceramic. Meanwhile, the electrical conduction mechanism was explored. The NTC behavior of the Y 1/2 Ce 1/2 TaO 4 and Y 1/3 Ce 1/3 Pr 1/3 TaO 4 ceramics is well described by the small polaron model at low temperatures, while it becomes dominated by oxygen ion migration at high temperatures. The results elucidate the effect of O V -induced formation of lattice distortions on the two charge conduction mechanisms. Temperature-dependent resistivity patterns manifest two charge conduction mechanisms. ( E a = 0.20-0.32 eV and 0.51-0.60 eV), which are intrinsically linked to the microstructure formation of polycrystalline materials. These findings offer novel insights into the regulation of NTC thermistors and the optimization of charge stability.