Preparation and proton conductivity of ultrafine Y-doped BaZrO₃ ceramics

Y-doped BaZrO₃ powders prepared by higherature solid state reactions often suffer the disadvantage of serious aggregation. In order to eliminate this disadvantage, planet-mill and sand-mill processing methods were employed. The results of particle-size determination and scanning electron microscopy images confirm that sand milling can efficiently eliminate the aggregation and produce ultrafine and well-dispersed Y-doped BaZrO₃ powders. Starting from powders treated by sand milling, completely densified Y-doped BaZrO₃ ceramics can be fabricated by sintering at a low temperature of 1640C for 15 h. Y-doped BaZrO₃ ceramics sintered from powders treated by sand-mill for 5 h possess an ultrafine crystal size and a higher density and proton conductivity compared to those treated for 2 h.