Synthesis and Microstructure Characterization of Gd- and Sc-Co-Doped BaTiO3 Nanopowders via Sol-Gel Method

The effects of rare-earth ions Sc3+ and Gd3+ on phase transition, microstructure and dielectric properties were investigated systematically. Gd-and Sc-co-doped nanopowders were synthesized via one-step sol-gel method. After xerogel was calcined at 800 °C for 2h, (1x)BaTiO3-xGdScO3 (0 x 0.06) nanopowders with narrow particle distribution was obtained. The nanopowders were then pressed into pellets and sintered at 1300~1450 °C respectively. The results indicated that the dielectric peaks of samples were broadened since double doping restrained the grain growth of BaTiO3 ceramics. For x = 0.06, pellets sintered at different temperatures can obtain a low curie temperature of 25 °C. Meanwhile, accompanied by an increasing sintering temperature, the dielectric loss of samples decreased gradually, achieving a optimal value of 1.1%.