Fast preparation route to high-performances textured Sr-doped Ca3Co4O9 thermoelectric materials through precursor powder modification

• 作者: Andres Sotelo Gustavo Garcia Idoia Urrutibeascoa Juan Carlos Diez Maria Antonieta Madre Miguel Angel Torres
• 来源期刊: 中国科学:材料科学(英文版)
• 学科: 工学
• 关键词: ceramics OXIDES HOT-PRESSING electrical properties power factor
• 年，卷（期）: 2019,（3）
• 页码范围: 399-406
• 页数: 8页
• 分类号: TB34

摘要

This work presents a short and very efficient method to produce high performance textured Ca3Co4O9 thermoelectric materials through initial powders modification. Microstructure has shown good grain orientation, and low porosity while slightly lower grain sizes were obtained in samples prepared from attrition milled powders. All samples show the high density of around 96% of the theoretical value.These similar characteristics are reflected in, approximately,the same electrical resistivity and Seebeck coefficient values for both types of samples. However, in spite of similar power factor(PF) at low temperatures, it is slightly higher at high temperature for the attrition milled samples. On the other hand, the processing time reduction(from 38 to 2 h) when using attrition milled precursors, leads to lower mechanical properties in these samples. All these data clearly point out to the similar characteristics of both kinds of samples, with a drastic processing time decrease when using attrition milled precursors, which is of the main economic importance when considering their industrial production.