微结构对Bi_2Sr_2Co_2O_y化合物电性能的影响

Influence of Microstructure on the Electrical Properties of Bi_2Sr_2Co_2O_y Compound

通过溶胶-凝胶法制备单相Bi2Sr2Co2Oy化合物,通过添加PEG20000和超声分散对化合物粉体微结构进行调控,采用SPS烧结得到了致密的块体.探索了微结构对Bi2Sr2Co2Oy化合物电性能的影响规律.结果表明,添加PEG20000和超声分散可以明显降低Bi2Sr2Co2Oy化合物粉体的晶粒尺寸,使烧结块体的晶粒尺寸大幅度减小,从而显著提高材料的电性能.温度为873K时,添加PEG20000并超声处理所制备样品烧结块体获得了最高ZT值0.041.

Single phase Bi2Sr2Co2Oy compound was synthesized by Sol-Gel method,using PEG20000 and ultrasonic treatment to optimize microstructure of powders,and bulk materials were gained after SPS technique.The influence of microstructure on electrical properties of Bi2Sr2Co2Oy compound was investigated.The results show that adding of PEG20000 and ultrasonic treatment can decrease the size of powders obviously,the grain size of bulk materials decreases greatly,so the electrical properties of material increased.Bulk materials synthesized from the powders prepared with adding PEG20000 and ultrasonic treatment gain the highest ZT value of 0.041 at 873K.