Lowering the sintering temperature of Gd-doped ceria by mechanochemical activation

摘要

Two kinds of Ce_(0.8)Gd_(0.2)O_(2-delta) pellets were synthesized by a solid-state reaction using two types of commercial CeO_2 and Gd_2O_3. In contrast to previous reports, pellets with a sintered density of 99% at 1300 °C were obtained regardless the powder used. Mechanochemical activation of the starting materials by 7 h of high energy milling, which resulted in particles several tens of nanometer in size, was effective in reducing the sintering temperature. Ce_(0.8)Gd_(0.2)O_(2-delta) pellets could be synthesized by direct sintering without calcination due to the homogeneous distribution of fine starting materials. The final phase was confirmed by the ionic conductivity, X-ray diffraction patterns and lattice parameters.